Devices and methods for cutting and evacuating tissue

ABSTRACT

Various medical devices and methods for cutting and/or evacuating tissue are provided. The devices and methods may utilize a reciprocating mechanism or motor powered by suction from a vacuum source. The medical devices and methods may be used on tissue in various regions of a patient&#39;s body and for treating various conditions, e.g., for performing a polypectomy or discectomy.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims benefit of priority to U.S. ProvisionalPatent Application Ser. No. 61/360,429 filed Jun. 30, 2010 and U.S.Provisional Patent Application Ser. No. 61/377,883 filed Aug. 27, 2010both of which are incorporated by reference herein in their entirety forall purposes.

FIELD OF THE INVENTION

The present devices and methods relate generally to medical devices andmethods for cutting and/or evacuating tissue from various regions of apatient's body.

BACKGROUND

Many common medical devices perform the function of resecting tissue.Suction, supplied by an external vacuum source is often used to evacuatetissue from the operative site.

Medical devices which cut and evacuate tissue are used in a variety ofprocedures, including ear, nose, and throat surgery, gynecologicalsurgery, spinal surgery, ophthalmic surgery, and many otherapplications. Depending on the procedure, the evacuated tissue may becollected for pathological analysis.

When applied to ear, nose, and throat surgery, tissue resecting devicesare commonly referred to as microdebriders.

Tissue incision may be performed by either a rotating cutter(unidirectional or oscillating) or a reciprocating cutter. In the caseof a rotating cutter, an electric motor is commonly used as the sourceof motion. In the case of a reciprocating cutter, motion may be producedby manual actuation, through a control such as a button or trigger, orpowered actuation using pulsed or valved compressed air. Each of thesepower sources has distinct disadvantages when used to power a resectingmedical device.

For example, when an electric motor is used to provide rotational motionof a cutter, the additional weight of the electric motor may causeoperator fatigue. Wires from an external power supply are inconvenientto make the connections and it is inconvenient to have the wiresattached to the device during use.

An electric motor increases the total cost of a device because of therelatively high cost of the motor itself and the cost of a power supply(in the case of an externally powered motor) or the cost of a rechargingunit (when rechargeable batteries are used). The addition of electricmotors makes sterilization of the device more difficult, e.g., becauseof the added mass to the device from the motors. Additionally, thepresence of batteries reduces the sterilization options available to themanufacturer, due to the heat generated by certain sterilizationtechniques. The presence of batteries adds potentially toxic chemicalsthat present additional challenges related to toxicity, sterilization,and device disposal.

Medical devices that include electric motors are often made to bere-usable which requires a system for reprocessing the device. Whenusing a manually actuated cutting device, the operator may experiencefatigue from repeated actuations. Additionally, manual actuations can beperformed only as quickly as the operator can actuate the cutter viamechanical input through a control and the time required to perform anadequate number of actuations may be excessive.

Electrically-powered microdebriders typically require an expensivecapital investment in a power console that is separate from thehandpiece. The capital cost of the power console, handpiece, anddisposable blades makes procedures such as a nasal polypectomy and otherprocedures cost prohibitive in a doctor's clinic setting.

Existing microdebriders are typically built with a handle of the devicein line with the shaft of the device, as a result, the handle and theoperator's hand may interfere with an endoscope and/or the camera.

Existing microdebriders expose a cutting blade to the end of the device.This may be disadvantageous when the operator loses sight of the end ofthe device and accidentally cuts or damages structures that come intocontact with it.

As a result of these limitations, it is impractical for Ear, Nose, andThroat physicians to remove nasal and sinus polyps or other tissue in anoffice or other setting using the current technology. Therefore,patients are left with the undesirable options of a course of steroidtreatments to reduce the size of the polyps (with associated steroidside effects), removal of the polyps in an ambulatory surgery center(cost prohibitive and therefore rarely performed as a stand-aloneprocedure), or leaving the polyps untreated and dealing with theassociated breathing obstruction.

BRIEF SUMMARY

Various medical devices and methods for cutting and/or evacuating tissuefrom various regions of a patient's body are provided herein

Various cutting device driven by various power sources are describedherein. In certain variations, a vacuum powered tissue cutting device isprovided. The device may include an elongate shaft having a proximalend, a distal end and a lumen defined therein. The distal end mayinclude an opening for receiving tissue. A cutter may be positionedwithin the elongate shaft, wherein the cutter is configured to beactuated to cut tissue. A chamber may be coupled to the proximal end ofthe elongate shaft. For example, the chamber may be coupled to theelongate shaft such that the elongate shaft remains fixed relative tothe chamber. The chamber may have a mechanism positioned therein,wherein the mechanism can be powered by suction created by a vacuumsource such that the mechanism produces an actuating motion which causesthe cutter to actuate, e.g., to reciprocate. In certain variations, acutter positioned within the elongate shaft may be reciprocated past theopening in the elongate shaft to cut tissue in the opening.

In certain variations, a method of cutting and/or removing tissue from asubject may include advancing a cutting device next to, near or to atarget tissue in the subject. The cutting device may have an elongateshaft and a cutter positioned within the elongate shaft. The cuttingdevice may be powered using suction created by a vacuum source such thatthe cutting device produces an actuating motion, which causes the cutterto actuate, e.g., reciprocate, to cut tissue. The cut tissue may beevacuated using the suction created by the vacuum source or may beotherwise removed. In certain variations, the method of cutting and/orremoving tissue may be utilized to perform a polypectomy or adiscectomy.

In certain variations, an apparatus for cutting or scraping tissue in asubject may be provided. The apparatus may include an end effector,wherein the end effector includes a scraping edge positioned on a distalend of the end effector. One or more scraping wings may be positioned atan angle relative to the scraping edge such that the scraping edge andscraping wings may be used to provide scraping motions in differentdirections.

In certain variations, devices, systems and methods for excising,cutting and/or evacuating tissue are provided. A variation of a devicemay include a cutter and a double action vacuum powered mechanism ormotor in which vacuum is used to actively reciprocate a piston connectedto the cutter. The vacuum powered motor may include a vacuum portconnected to a vacuum source, a shuttle piston, a drive piston coupledto the shuttle piston, and a chamber for receiving the drive piston, thechamber having proximal and distal sides. The drive piston may be setinto reciprocating motion through the creation of differential pressureon either side of the piston by alternating evacuation, through thevacuum port, within the two sides of the piston chamber. The motion ofthe drive piston may effect translation of the shuttle piston, causingthe shuttle piston to alternate between positions of opening and closingthe vacuum port to the proximal and distal sides of the piston chamberto alternate evacuation of each side of the chamber. The actuatingmotion, e.g., reciprocating motion, of the drive piston may be used toreciprocate or rotate the cutter.

In certain variations, a cutting or scraping component may be positionedor located at or near a distal end of a rigid or flexible end effectorwhich may be utilized to excise, scrape or cut tissue. The end effectormay be curved or straight. The end effector may include a shaft, areciprocating cutter and/or a scraping edge positioned on the shaft oron the reciprocating cutter.

In certain variations, a cutter may be positioned at or near the distalend of a malleable shaft that may be shaped by the operator to acurvature suitable to access the desired anatomical location.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1A illustrates a side view of a variation of a cutting device.

FIG. 1B illustrates a side view of the cutting device of FIG. 1A withthe right hand portion of the chamber hidden.

FIG. 1C illustrates a side view of the cutting device of FIG. 1B withthe rigid sleeve and elongate shaft hidden to show the evacuation shaft.

FIG. 1D illustrates a side view of the cutting device of FIG. 1B withthe manifold of the vacuum powered mechanism hidden.

FIG. 1E illustrates a side view of the cutting device of FIG. 1B withthe collection chamber hidden to show a filter.

FIG. 1F illustrates a magnified view the elongate shaft of the cuttingdevice of FIG. 1B having multiple lumens.

FIG. 1G illustrates a magnified view of the cutter of the cutting deviceof FIG. 1B.

FIG. 1H illustrates a vacuum source coupled to a variation of thecutting device.

FIG. 2A illustrates a side view of a variation of a vacuum poweredmechanism.

FIG. 2B illustrates a cross sectional view of the vacuum poweredmechanism of FIG. 2A.

FIG. 2C illustrates an opposite side view of the vacuum poweredmechanism of FIG. 2A.

FIG. 2D illustrates a front view of the vacuum powered mechanism of FIG.2A.

FIG. 2E illustrates a rear view of the vacuum powered mechanism of FIG.

FIGS. 2F-2G illustrate side and prospective cross sectional views of thevacuum powered mechanism of FIG. 2A in a first position.

FIGS. 2H-2I illustrate side and prospective cross sectional views of thevacuum powered mechanism of FIG. 2A in a second position.

FIG. 3A illustrates a cross sectional view of a variation of a doubleaction vacuum powered mechanism having a bi-stable switch in a proximalposition.

FIG. 3B illustrates a cross sectional view of the double action vacuumpowered mechanism having a bi-stable switch of FIG. 3A in a distalposition.

FIG. 4A illustrates the cross sectional view of a variation of a doubleaction vacuum powered mechanism in a proximal position.

FIG. 4B illustrates a cross sectional view of the double action vacuumpowered mechanism of FIG. 4A in a distal position.

FIG. 5A illustrates a cross sectional view of a variation of a singleaction vacuum powered mechanism using a spring return system in aproximal position.

FIG. 5B illustrates a cross sectional view of a single action vacuumpowered mechanisms of FIG. 5A in a distal position.

FIG. 6 illustrates a side view of a variation of an end effector.

FIG. 7 illustrates a side view of a variation of an end effector.

FIG. 8 illustrates a flow chart of a variation of a method for cuttingand removing tissue using a vacuum powered cutting device.

FIG. 9 illustrates a flow chart of a variation of a method forperforming a polypectomy using a vacuum powered cutting device.

FIG. 10 illustrates a flow chart of a variation of a method forperforming a discectomy using a vacuum powered cutting device.

DETAILED DESCRIPTION

Variations of the devices are best understood from the detaileddescription when read in conjunction with the accompanying drawings. Itis emphasized that, according to common practice, the various featuresof the drawings may not be to-scale. On the contrary, the dimensions ofthe various features may be arbitrarily expanded or reduced for clarity.The drawings are taken for illustrative purposes only and are notintended to define or limit the scope of the claims to that which isshown.

Various cutting devices and methods for cutting, resecting, incising orexcising tissue are described herein. In certain variations a cuttingdevice may include a mechanism or motor driven or powered by a varietyof different power sources, e.g., suction from a vacuum source,pneumatic, fluid pressure (e.g. hydraulic), compressed air, batterypower or electrical power or gas power or any combination thereof. Themechanism or motor may create a reciprocating or rotational motionoutput in any direction which causes a cutter on or in the cuttingdevice to actuate, e.g., reciprocate or rotate, to cut tissue. Thecutting device may be utilized to cut, resect, incise or excise varioustypes of tissue located in various regions of a patient's body. Forexample, the cutting device may be utilized to perform a polypectomy ina patient for removal of one or more polyps.

In certain variations, a cutting device powered by suction from a vacuumsource (either external or internal) is provided. The cutting device mayinclude an elongate shaft. The elongate shaft may have a proximal end, adistal end and one or more lumens positioned within or along theelongate shaft. The distal end of the elongate shaft may include anopening or window for receiving tissue. The device may include a cutterfor cutting tissue. A cutter may be positioned within or on the elongateshaft. The cutter may be actuated, reciprocated, e.g., axially along thelongitudinal axis of the elongate shaft, or rotated to cut tissue. Achamber may be coupled to the proximal end of the elongate shaft. Theelongate shaft may be coupled to the chamber such that that the elongateshaft or a cannula remains fixed or immovable relative to the chamber,e.g., while the cutter, on or in the elongate shaft or cannula, is beingreciprocated or otherwise motivated or during actuation, reciprocationor rotation of the cutter.

A mechanism or motor may be positioned within the chamber. The mechanismmay be powered by suction created by a vacuum source, which causes themechanism to produce a reciprocating motion. In certain variations, themechanism may be powered solely by suction created by the vacuum source,e.g., without the use of electricity or pressurized air or fluid topower the mechanism. Additional connections for electrical orpneumatic/hydraulic power may not be required. The mechanism may includea piston which is put into reciprocating or reciprocating linear motionby suction from the vacuum source. The reciprocating motion outputproduced by the mechanism causes the cutter (connected to the mechanism)to actuate, e.g., to reciprocate or to rotate. In certain variations,the cutter may be reciprocated back and forth in a linear motion, e.g.,axially, or along the longitudinal axis of the elongate shaft. In othervariations, linear reciprocating motion from the mechanism may betranslated into rotational motion of the cutter. The cutting device mayinclude a port or valve for connecting the vacuum source to the cuttingdevice to provide suction to the cutting device.

The suction from a vacuum source may draw tissue into the opening in theelongate shaft. The cutter may be reciprocated or rotated past theopening in the elongate shaft, thereby cutting the tissue which is drawninto the opening of the elongate shaft. The cutting device may includean evacuation lumen for evacuating cut tissue using suction created bythe vacuum source. In certain variations, the tissue may be otherwiseremoved without using evacuation to remove the tissue.

In certain variations, a lumen for delivering irrigant or fluid may beprovided. For example, the elongate shaft may include a lumen fordelivering irrigant to the distal end of an evacuation lumen in theelongate shaft or to an opening of the elongate shaft or to a cutter.The irrigant may flow constantly through the lumen, or it may flowthrough the lumen only when suction from the vacuum source is present todraw the irrigant through the irrigant lumen. The cutting device mayinclude a reservoir filled with water or other irrigant positioned withthe cutting device or the irrigant may be provided from an externalsupply. For example, a syringe filled with irrigant, e.g., water, may beconnected to the cutting device or an elevated container or bag maysupply irrigant to the cutting device or to the site of treatment. Theirrigant may begin to flow through the cutting device when suction ispresent in a lumen within the elongate shaft, at an irrigant port, whichmay be located within the shaft lumen near the opening of the elongateshaft. The irrigant may be drawn to the distal end of an evacuationlumen in the elongate shaft or to the opening of the elongate shaft,where it lubricates tissue and a lumen within the shaft, e.g., a tissueevacuation lumen, to facilitate evacuation of the cut tissue.

The cutting device may include a handle, such that the cutting devicemay be handheld. For example, the chamber of the cutting device may bein the form of a handle. The handle may be positioned or set at an anglerelative to the elongate shaft. This arrangement of the handle orchamber relative to the elongate shaft may provide a clear orsubstantially clear line of site above and/or to the sides of theelongate shaft. The angled arrangement may reduce interference withother medical devices or instruments that a user may utilize during atissue cutting procedure, e.g. an endoscope and associated cables. Thisangled arrangement may also provide optimal user comfort. The handle mayhave an ergonomic design to provide comfort and ease of use. A curved orangled neck portion may extend from the chamber or handle, for receivingor holding the elongate shaft.

A tissue collection chamber may be provided. For example, a tissuecollection chamber may be integrated in the chamber or handle of thecutting device or may be otherwise connected or attached to the cuttingdevice. The tissue collection chamber may be removable from the cuttingdevice. The removable tissue collection chamber may allow tissuecollected therein to be biopsied, studied or a diagnosis of pathologymay be performed on the collected tissue. Removal of the tissuecollection chamber and/or filter may result in the device beingdisabled, e.g., where the tissue collection chamber may not bereassembled to the device. This may prevent the device from being reusedor used on more than one patient to minimize or prevent the associatedrisks of transmitting pathogens from one patient to another or infectinganother patient. For example, the device may be disabled where theinternal vacuum lines are sheered when the tissue collection chamber isremoved from the handle. As a result, the tissue collection chambercannot be reassembled to the device thereby rendering the deviceuseless. The device may be fully or partially disposable.

In other variations, a tissue collection chamber may be reusable, wherethe tissue collection chamber may be removed, sterilized and thenreassembled or reattached to the cutting device for continued use.

Various configurations of the elongate shaft are contemplated. Incertain variations, at least a portion of the elongate shaft or theentire elongate shaft may be malleable or otherwise adjustable. Forexample, the distal end of the elongate shaft or the section of theelongate shaft where tissue cutting is performed may be malleable orflexible such that portion of the elongate shaft may be adjusted ormanipulated by the user, e.g., hand adjustable. The malleable portion ofthe elongate shaft may be manipulated into a variety of shapes or curvessuch that the cutting device, e.g., the cutter or cutter opening, mayaccess or be positioned in a variety of anatomical locations to cutand/or remove tissue. The malleable portion of the elongate shaft may beadjusted or manipulated before or during operation by the user intovarious positions or configurations, ranging from, straight to angled orcurved. The shaft may be manually, automatically or roboticallyadjusted. The shaft may be adjusted without the need for additionaltools or attachments to change or affect the shape or position of theshaft, such that the positioning for cutting and cutting may beperformed using a single device. In other variations, a tool orattachment may optionally be utilized to adjust or manipulate anelongate shaft for cutting.

A cutter may have various shapes and configuration, e.g., the cutter maybe in the form of a cutting blade or pipe or tube positioned within theelongate shaft. A cutter may be positioned in the cutting device suchthat the cutter can reciprocate past an opening or cutting window in theelongate shaft. In certain variations, the cutter may be positionedwithin or on the elongate shaft such that the cutting blade is notexposed on an outside of the opening or window in the elongate shaft orbeyond the distal tip of the elongate shaft. This arrangement mayprovide safety to patients and minimize or prevent the risk ofinadvertently cutting or puncturing tissue in a patient during thetissue cutting procedure or during advancement of the cutting device tothe target site in a patient for treatment. In certain variations, theanvil may protect a cutter such that it is not exposed, therebyproviding safety to patients.

A sufficient vacuum source for operating or powering any of the cuttingdevices described herein may be the vacuum source provided in moststandard operating rooms, physician's offices, clinics or outpatientsurgery centers. For example, many physicians'offices have vacuum pumpscapable of generating vacuum in the ranges of 10 to 25 inches of mercury(in HG), e.g., about 22 inches of mercury (in Hg) and/or at about 28 toabout 40 liters per minute (LPM) flow rate. The various cutting devicesdescribed herein may utilize vacuum sources or vacuum pumps operating inthe above performance ranges to effectively operate and cut tissuewithout additional power inputs or supply requirements needed. Forexample, suction provided by such vacuum sources may move, actuate,reciprocate or otherwise operate the mechanism of a cutting deviceand/or the cutter at a speed or rate ranging from about 250 to about2500 cycles/min or about 500 to 1200 cycles per minute or less thanabout 1200 cycles per minute. These rates are slower than the rates thatwould be provided by a typical electrically powered motor, yet providethe control and power to effectively and safely operate and reciprocatethe cutter of the cutting devices described herein to cut, resect,and/or excise tissue in various regions in a patient, e.g., to cut andremove polyps positioned in the nasal or sinus cavity of a patient in asafe, controlled and effective manner.

In certain variations, a cutting device may be connected solely to avacuum source, and optionally, to an irrigant source. The vacuum sourcemay be connected to the cutting device such that suction supplied by thevacuum source drives or powers the mechanism of the cutting device,draws tissue into the opening in the elongate shaft or otherwise intothe path of a cutter, draws irrigant from a reservoir or other sourcethrough the cutting device or through a lumen in or on the cuttingdevice, or to the cutting device and/or evacuates cut tissue for removalfrom a patient.

Various vacuum powered mechanism for use in the various cutting devicesdescribed herein, to drive or actuate a cutter, are also describedherein. In certain variations, a vacuum powered or vacuum drivenmechanism may include one or more pistons, wherein suction is applied toboth sides of the piston in an alternating manner to cause the piston toreciprocate. The piston is coupled or connected (directly or indirectly)to the cutter, thereby causing the cutter to reciprocate. In anothervariation, suction may be applied to one side of the piston and a springforce in a vacuum powered mechanism may be applied to the other side ofthe piston, to cause the piston to reciprocate. The reciprocating pistoncauses the cutter to reciprocate.

In certain variations, a hand-held, fully disposable powered medicaldevice capable of resecting tissue in the human body is provided. Thedevice is powered by an internal mechanism that is powered by suctionfrom an external vacuum source. The mechanism produces reciprocatingmotion that may be used to move a cutter back-and-forth past an openingin a shaft. A portion of the suction from the external vacuum source isrouted through the shaft and draws tissue into the window where it isexcised by the cutter. The tissue is then evacuated through the shaftand into a tissue collection chamber on the handle of the device. Thesuction in the shaft also draws irrigant into the lumen of the shaft,where it lubricates the tissue and shaft lumen to facilitate evacuationof the tissue.

In certain variations, the cutting devices or mechanisms describedherein may be powered by a vacuum source where the devices have anefficient use of supplied vacuum suction to the device, e.g., with noneof the supplied suction going unused. In certain variations, a cuttingdevice may be powered by constant delivery of vacuum or suction. Incertain variations, a cutting device may be manufactured of all orsubstantially all mechanical components reducing costs formanufacturing.

In certain variations, a cutter may be positioned at or near the distalend of a flexible shaft that has a preformed or predetermined curvature.The shaft may be adapted for insertion into a cannula where the distalend of the shaft may advance from the cannula toward a target site andwhere the shaft allows its predetermined curvature to position thedistal end of the shaft near the target site.

Exemplary Cutting Devices

FIG. 1A shows one variation of a vacuum powered cutting device.Referring to FIGS. 1B-1E, the cutting device 10 includes an elongateshaft 12. The elongate shaft 12 may include a rigid sleeve 14 thatprovides rigidity to the elongate shaft. The elongate shaft may includea window or cutting window or opening 16 positioned at or near a distalend of the elongate shaft. An evacuation shaft 17 may be positionedwithin the elongate shaft 12. A cutter 18 may be positioned within theelongate shaft 12 such that it may be reciprocated past the opening 16.In this particular variation, the cutter 18 is formed at the distal endof the evacuation shaft 17, but other types of cutters are contemplated,e.g., the cutter 18 may extend from a wire or blade positioned in theelongate shaft 12.

One or more lumens may be positioned within the elongate shaft 12 (SeeFIG. 1F). Elongate shaft 12 may include an irrigant lumen. An irrigantline (not shown) may connect to the proximal end 13 of the elongateshaft 12, to supply irrigant from an internal or external reservoir orirrigant source, through an irrigant lumen in the elongate shaft 12, tothe distal end of an evacuation lumen in the elongate shaft or to theopening 16 of the elongate shaft 12. For example, the irrigant may bedrawn to the opening 16 of the elongate shaft 12, where it lubricatestissue and the evacuation lumen, to facilitate evacuation of the cuttissue. Optionally, the elongate shaft 12 may include a malleableportion, for example at its distal end, which can be manipulated oradjusted to provide various shapes and configurations to the elongateshaft 12 to position a cutter in various regions of the body.Optionally, one or more wires 15 may positioned in the elongate shaft12, which may serve to hold the malleable portion of the shaft in adesired position. A rigid sleeve 14 may be placed over other portions ofthe elongate shaft 12 to provide rigidity.

The elongate shaft 12 may extend from a chamber 20. The chamber 20 mayprovide a handle or grip for a user. The chamber 20 may include a tissuecollection chamber 22. The evacuation shaft 17 may extend into thechamber 20, such that one or more lumens of the evacuation shaft 17empties into the tissue collection chamber 22 either directly orindirectly, e.g., via another tube or pipe (not shown), connecting theevacuation shaft 12 to a first vacuum chamber port 21. The tissuecollection chamber 22 may include a filter 25 for filtering tissuecollected therein. The tissue collection chamber 22 may be integratedinto the chamber 20 such that removal of the tissue collection chamber22 disables the cutting device 10. In certain variations, the elongateshaft 12 may be coupled or connected to the chamber 20 such that theelongate shaft 12 remains fixed relative to the chamber 20. For example,the elongate shaft 12 may be fixed such that it is not motivated orreciprocated by the mechanism 30 or motor described below.

A vacuum powered mechanism 30 is positioned within the chamber 20. FIGS.2A-2I show various views of the vacuum powered mechanism 30. Themechanism 30 includes a shuttle piston 32 and a drive piston 34. Thepistons may be arranged in various configuration, e.g., in parallel toone another. A bi-stable switch 36 may be connected to the shuttlepiston 32 and the drive piston 34. The bi-stable switch 36 having aswitch spring 37 may be connected to the drive piston 34 and the shuttlepiston 32 either directly or via a piston clamp 35 connected to theswitch spring 37 or bi-stable switch 36. Actuation of the bi-stableswitch 36 by the drive piston 34, which is motivated or reciprocated bysuction created by the vacuum source, may reverse or move the shuttlepiston 32 in either the proximal or distal directions (i.e., toward thedistal end of the cutting device or toward the proximal end of thecutting device.) When the shuttle piston 32 moves from one end of its'travel extremity to the opposite end of its' travel extremity, theevacuated side of a drive piston chamber 42 is vented to allowatmospheric air to flow into the drive piston chamber 42 while theopposite side of the drive piston chamber 42 is shut off fromatmospheric air and evacuated. As a result, the drive piston 34 ismotivated to move in the opposite direction until the bi-stable switch36 is actuated and the shuttle piston 32 reverses. The shuttle piston 32and the drive piston 34 are positioned in a manifold 38. The manifold 38includes a drive piston chamber 44 and a shuttle piston chamber 42. Thebi-stable switch 36 may ensure a reliable transition of the shuttlepiston 32 or valve on the shuttle piston past or completely past ashuttle chamber vacuum supply port 47 to prevent unstable flutter of theshuttle piston 32 and possible mechanism 30 or motor stall.

As shown in the various cross sectional views of FIG. 2B and FIGS.2F-2I, at least a portion of the drive piston 34 is positioned in thedrive piston chamber 44 and at least a portion of the shuttle piston 32is positioned in shuttle piston chamber 42. The drive piston chamber 44and the shuttle piston chamber 42 are in fluid communication with eachother via first and second vacuum slots 45 and 46.

A shuttle chamber vacuum supply port 47 is provided to connect a vacuumsource, via a tube or line (not shown), to the mechanism 30 to providesuction to the mechanism 30. FIG. 1H shows a vacuum source coupled to avariation of the cutting device 10. The tube or line may be connected toa second vacuum chamber port 28 (shown in FIGS. 1B-1D) and/or theshuttle chamber vacuum supply port 47. The shuttle chamber vacuum supplyport 47 provides entry into the shuttle piston chamber 42, such that thevacuum source can be in fluid communication with the shuttle pistonchamber 42 and evacuate the shuttle piston chamber 42 and/or the drivepiston chamber 44, to power and motivate the drive piston 34 and/or theshuttle piston 32, as described in further detail herein. Details of avacuum powered mechanism are also provided below with reference to FIGS.3A-3B.

The mechanism 30 may be activated and the drive piston 34 reciprocatedby suction from the vacuum source as soon as the vacuum source isconnected to the cutting device 10 and the vacuum source is activated.Referring back to FIGS. 1A-1E, the cutting device 10 may also include atrigger 26 positioned on the chamber 20 in a location such that thetrigger 26 can be conveniently or ergonomically actuated by a user'sfinger as the user holds the cutting device 10. When the trigger 26 isin the “on” position, the trigger 26 is disengaged from the shuttlepiston 32, allowing the shuttle piston 32 to reciprocate due tomotivation of the bi-stable switch 36 which is in turn motivated by themovement of the drive piston 34. When the trigger 26 is actuated into an“off” position, the trigger 26 may interact with or engage the shuttlepiston 32, which causes the shuttle piston 32 and drive piston 34 tostall or stop such that the cutter 18 is stopped in a position proximalto the opening 16 thereby leaving the opening 16 open. This allows thedevice 10 to be used for suction or evacuation through opening 16, evenwhen the mechanism 30 and cutter 18 are not activated, as the vacuumsource may remain activated and connected to the cutting device 10,supplying suction through a lumen of the evacuation shaft 17. In certainvariations, suction may not be supplied through the lumen of theevacuation shaft during cutting.

The vacuum source may be connected to the cutting device 10 at theexternal vacuum port 29. The external vacuum port 29 is in fluidcommunication with the tissue collection chamber 22 and the first vacuumchamber port 21, supplying suction to the lumen of the evacuation shaft.The external vacuum port 29 is in fluid communication with the secondvacuum chamber port 28, supplying suction through the shuttle chambervacuum supply port 47 to the shuttle piston chamber 42 and the drivepiston chamber 44, to motivate, reciprocate and/or power drive piston34, which motivates or reciprocates the bi-stable switch 36 and cutter18, which is connected to the vacuum powered mechanism 30 eitherdirectly or indirectly.

In use, the elongate shaft 12 of the cutting device 10 may be insertedinto the desired location or area in a patient. The vacuum source isconnected to the cutting device 10, supplying suction to the mechanism30, causing the drive piston 34 to reciprocate. The drive piston 34causes one side of the bi-stable switch 36 to move either proximally ordistally which increases the tension on the extension spring 37. Theincreased tension on the extension spring 37 causes the adjacent side ofthe bi-stable switch 36 and the shuttle piston to move proximally ordistally to decrease the length of the extension spring 37. When theseal on the shuttle piston or shuttle piston 32 moves past the suctionport 47, the vacuum or suction in the shuttle chamber 42 reverses to theopposite side of the drive piston 34 while atmospheric air is allowed toflow into the side of the shuttle chamber 42 that is not evacuated,thereby motivating the drive piston 34 to move toward the evacuatedside. (As shown for example in FIG. 2B). The evacuation shaft 17 isconnected to the drive piston 34. The evacuation shaft 17 may beconnected directly to the drive piston 34 or the evacuation shaft 17 maybe connected to sleeves, tubes or other shafts that are connected to thedrive piston 34. For example, the piston clamp 35 may connect theevacuation shaft 17 to the drive piston 34.

As stated supra, the cutter 18 is formed at the distal tip of theevacuation shaft 17. Once the vacuum source is connected to the cuttingdevice 10 and the trigger 26 is positioned in the “on” position suchthat it is disengaged from the shuttle piston 32, suction applied to themechanism 30 causes the drive piston 34 (and consequently the shuttlepiston 32 as described above) to reciprocate, which causes theevacuation shaft 17 and the cutter 18 to reciprocate, driving the cutter18 back and forth, e.g., in a linear or axial motion along thelongitudinal axis of the elongate shaft, past the opening 16 in theelongate shaft 12. A close up of a variation of a cutting window isshown in FIG. 1G. At the same time, suction may be supplied from thevacuum source through a lumen of the evacuation shaft 17, to draw tissueinto the opening 16, where the tissue is then cut by the reciprocatingcutter 18. Optionally, the suction in the evacuation lumen, may alsoevacuate the cut tissue and deliver it to the tissue collection chamber22.

While the reciprocating motion of the drive piston 34 of the mechanism30 is translated to the cutter 18 via the evacuation shaft 17 in thevariation described above, other components for translating suchreciprocating motion are also contemplated. For example a cutter mayextend from a wire or blade or any other extension or member which isconnected to the mechanism 30, e.g., via the drive piston 34 or pistonclaim 35. In certain variations, the cutter 18 may be directly orindirectly connected to the mechanism 30 or the drive piston 34 or theshuttle piston 32 or the bi-stable switch 36.

In certain variations, a loop or extension may be provided in theevacuation shaft 17 or in a tube or pipe connecting the evacuation shaft17 to the first vacuum chamber port 21, providing extra length that maymove or change shape such that at least a portion of the evacuationshaft 17 or tube or pipe that is connected to the first vacuum chamberport 21 does not move or reciprocate or become dislodged when theevacuation shaft 17 is being reciprocated or motivated by the mechanism30.

In certain variations, a method of cutting and removing tissue from asubject may include advancing a cutting device at, next to, in or near atarget tissue in the subject. The cutting device may include an elongateshaft and a cutter positioned within or on the elongate shaft. Theelongate shaft may be advanced into the subject to access the targettissue and to position the cutter at, next to, in or near the targettissue to cut and/or remove the tissue. The cutting device includes amechanism or motor which is powered or driven by suction created by avacuum source. The suction from the vacuum source powers the mechanismcausing it to produce a reciprocating or rotating motion which causesthe cutter to reciprocate or rotate to cut tissue. The tissue mayoptionally be evacuated using suction created by the vacuum source. Thecut tissue may optionally be gathered or collected with the cuttingdevice. In certain variations, suction or vacuum may be turned off ornot supplied to the opening and the tissue may be otherwise removed. Incertain variations, the suction from the vacuum source may draw tissueinto an opening on the elongate shaft. The cutter may be reciprocated orrotated past the opening to cut the tissue drawn into the opening on theelongate shaft. In certain variations suction from the vacuum source maydraw an irrigant to the distal end of an evacuation lumen in theelongate shaft or to the opening of the elongate shaft, where itlubricates tissue and/or the evacuation lumen, to facilitate evacuationof the cut tissue. In certain variations, the cutting device may includea chamber in which the mechanism is positioned. The elongate shaft maybe attached to the chamber such that it remains in a fixed positionrelative to the chamber while the mechanism is producing a reciprocatingmotion and reciprocating a cutter shaft or evacuation shaft positionedwithin the elongate shaft.

In certain variations, a method of cutting, resecting or excising tissuein a patient may include attaching the cutting device to a vacuum source(internal or external) and optionally to a source of irrigant. Thevacuum source supplies suction that may power or motivate the mechanismor motor of the cutting device, draw tissue into the path of a cutter orcutting blade, draw irrigant from an irrigant source to the site ofcutting or excision or near the cutter, and/or evacuate cut tissue fromthe patient.

In certain variations, a method for performing a polypectomy in asubject may include advancing a cutting device at, to, next to, in ornear a target polyp. Polyps may be located in various regions of apatient. For example, nasal or sinus polyps may be cut and/or removed byadvancing the cutting device into the nasal cavity and positioning acutter at, next to, in or near the polyp. The cutting device may includean elongate shaft and a cutter positioned within or on the elongateshaft. The elongate shaft of the cutting device may be advanced into thenasal or sinus cavity to access the polyp and position the cutter nearthe polyp. The cutting device includes a mechanism or motor which ispowered by suction created by a vacuum source. The suction from thevacuum source powers the mechanism causing it to produce a reciprocatingor rotating motion which causes the cutter to reciprocate or rotate tocut tissue. The tissue may optionally be evacuated using suction createdby the vacuum source. The cut tissue may optionally be gathered orcollected with the cutting device. In certain variations, suction orvacuum may be turned off or not supplied to the opening and the tissuemay be otherwise removed. In certain variations, the suction from thevacuum source may draw tissue into an opening on the elongate shaft. Thecutter may be reciprocated past the opening to cut the polyp tissuedrawn into the opening on the elongate shaft. In certain variations, themechanism may be powered solely by suction from a vacuum source, withoutrequiring the use of compressed or pressurized air or electric power tosupply power.

In certain variations, a method for performing a discectomy in a subjectmay include advancing a cutting device at, to, next to, in or near adisc in a spine. For example, a disc annulus or nucleus may be cut byadvancing the cutting device into or next to the disc and positioning acutter at, next to, in or near the disc. The cutting device may includean elongate shaft and a cutter positioned within or on the elongateshaft. The elongate shaft of the cutting device may be advanced into ornext to the disc to position the cutter. The cutting device includes amechanism or motor which is powered by suction created by a vacuumsource. The suction from the vacuum source powers the mechanism causingit to produce a reciprocating or rotating motion which causes the cutterto reciprocate or rotate to cut tissue. The tissue may optionally beevacuated using suction created by the vacuum source. The cut tissue mayoptionally be gathered or collected with the cutting device. In certainvariations, suction or vacuum may be turned off or not supplied to theopening and the tissue may be otherwise removed. In certain variations,the suction from the vacuum source may draw tissue into an opening onthe elongate shaft. The cutter may be reciprocated past the opening tocut the disc tissue drawn into the opening on the elongate shaft. Incertain variations, the mechanism may be powered solely by suction froma vacuum source, without requiring the use of compressed or pressurizedair or electric power to supply power.

In certain variations, a user may cut tissue by positioning a cuttingwindow on an elongate shaft against the tissue to be resected andactuate a switch or trigger to allow the mechanism to reciprocate. Thiscauses a cutting blade to move back-and-forth past the cutting window.As tissue is drawn into the cutting window by suction, the blade shavesthe portion of tissue that is in the path of the cutting blade. Thetissue is then evacuated through the lumen of the shaft that isconnected to the blade and is deposited in a tissue collection chamber.

The cutting devices described herein may be utilizing for a variety ofprocedures as described supra. The cutting device may be advanced orinserted into or through existing orifices, cavities or passages, e.g.,a nasal cavity, airway, respiratory passage, reproductive pathways,intestinal pathways or other pathways. The cutting devices may beadvanced or inserted into a patient percutaneously, intraluminally or inany minimally invasive manner to perform a procedure in or on a subject.Optionally, a cutting device may be utilized through a surgical incisionor site.

The various cutting devices described herein, e.g., a handheld and/orportable cutting device, allow for cutting and/or removal of tissue,e.g., a nasal polyp, by providing a low cost, disposable device thatallows the tissue cutting procedure to take place in a manner that issafe, quick, and inexpensive. The cutting device does not requiresignificant setup time, or the inconvenience and expense associated withcapital equipment. In-office tissue removal using a cutting device maybe performed using local anesthetic as compared to general anestheticwhich is used in ambulatory surgery centers. For example, a cuttingdevice may be utilized to perform nasal and sinus polyp removal in adoctor's office setting. While the cutting devices described herein maybe used to perform a polypectomy, they can also be used for tissueresection procedures in other locations of the body, e.g., including forear, nose, and throat surgery, gynecological surgery, spinal surgery,general surgery and ophthalmic surgery.

A cutting device that uses a vacuum source, e.g., an external vacuumsource, to power an actuating or reciprocating mechanism or motor thatis connected to a cutter, thereby translating the reciprocating motionto the cutter to cause the cutter to reciprocate provides a number ofadvantages and efficiencies. The cutting device does not require aninvestment in capital equipment, such as electric powered consoles, thusproviding a user with a substantial cost savings. Capital equipmentrequires valuable storage space when not in use as well as service andmaintenance in the facilities where it is used. The cutting device alsoallows a manufacturer to make continuous improvements without beingconstrained by installed capital equipment.

The cutting devices described herein may be manufactured using low costcomponents and assembly techniques, making the cost of the device muchlower than a cutting device which utilizes an electric motor. Theelongate shaft may be constructed from a variety of materials. Forexample, a combination of metal and plastic components that are notsusceptible to heat buildup resulting from friction between movingcomponents may be utilized.

Using a vacuum source as the power source to provide both tissueevacuation and mechanical motion to cut tissue eliminates or reduces thenumber of additional or separate connections, wires or tubes that wouldotherwise be required to provide electrical or other pneumatic power,such as pressurized or compressed air, and evacuation. A standaloneconsole to transfer the electrical or other pneumatic power may not berequired to operate the cutting device.

In certain variations, a single tube connects the vacuum source to thecutting device to serve the functions of tissue cutting, evacuation, andto power the mechanism which actuates the reciprocating cutter. A singletube simplifies connections required for device operation and reducesthe number of tubes attached to the device thereby reducing the“clutter” and unwieldiness caused by multiple tubes and wire connectionsextending from a device.

In certain variations, a splitting connection within the handle may beprovided which connects the vacuum to both a tissue evacuation tube andthe vacuum powered mechanism. The splitting connection may come inmultiple forms such as multiple connections to the tissue collectionchamber where a single connection to a source of vacuum creates a vacuumwithin a Filter Chamber. Another form of a splitting connection may be a“Y” or “T” shaped junction that joins two fluid paths into a singlepath. As a result of sharing the vacuum source between the mechanism andthe evacuation tube and cutting window or opening, the vacuum performseveral functions within the device: powers the mechanism which causesthe cutter to reciprocate, draws tissue into an opening or cuttingwindow such that it may be excised, evacuates the excised tissue throughthe tissue evacuation shaft to a filter or tissue collection chamber.

Where an external vacuum source is connected to the device to providesuction to facilitate tissue cutting and evacuation, an additional powersource such as electricity, compressed air, or mechanical input by theoperator may not be required.

Using vacuum power to actuate the cutter reduces operator fatiguecompared to a system requiring the operator to manually actuate thereciprocating mechanism. The rate at which the cutter actuates, relativeto manual actuation, may be significantly increased, thereby reducingthe time required to complete a tissue resection or excision procedure.Also, the control for the rate of actuation of the mechanism or motormay be moved from a “primary” position, such as a trigger or button, toa “secondary” position, e.g., on the device handle. As a result, the“primary control” may be utilized to control other parameters, e.g., therate at which the cutter actuates, the radius of curvature of theelongate shaft, or to control an electrocautery system that may beincluded in or on the device. A knob, trigger, roller clamp, or othercontrol interfaces may be used to control the rate at which the vacuumdriven mechanism or motor actuates or reciprocates. These options allowthe device to be designed in a variety of configurations to suit varioussurgical specialties or personal preferences.

The cutting devices described herein may have a relatively low mass,providing ease of use and comfort during short or long procedures. Thecutting devices may be easily sterilized using commonly usedsterilization techniques such as electron beam radiation, gammaradiation, or Ethylene Oxide gas.

In certain variations, a pneumatic logic sequence that maintains highvacuum throughout the mechanism, motor or engine cycle by never ventingthe vacuum source to the atmosphere may be provided. As a result, thevacuum suction or pressure that facilitates cutting and evacuation doesnot decrease while the mechanism or motor reciprocates.

In certain variations, the cutting device may include cautery, e.g., anelectrocautery system or wires heated via monopolar or bipolarradiofrequency, or by resistive heating. The cautery may be located ator near the distal extremity of the device to cauterize tissue tocontrol bleeding at the site where tissue has been cut or excised.Having a cautery obviates the need to remove the device from anoperative site and replace it with a separate electrocautery device,thereby improving speed and ease-of-use for the operator while reducingblood loss for the patient. The electrocautery system may be powered bywires that run the length of the elongate shaft through an internallumen within the elongate shaft. The wires may be connected to a powerconsole or optionally the power source may be located in the handle orchamber of the cutting device.

In certain variations, a resistive heating electrocautery system may beprovided on the distal tip of an elongate shaft. The power source forthe electrocautery system may be located in the handle of the cuttingdevice and may be connected to the distal tip of the shaft by wires thatrun the length of the shaft. The power source may include one or morebatteries that provide electrical energy to the distal end of thedevice. The electrical energy may be converted to heat energy whenpassed through a heating element such as a tungsten wire.

As described supra, in certain variations, a cutting device may includea malleable elongate shaft or at least a partially malleable elongateshaft that may be hand adjustable. A flexible or malleable shaftprovides access to multiple anatomical locations using a single device,thereby improving cost efficiency and convenience for the operator. Oneor more annealed wires may be positioned in an elongate shaft orflexible shaft to allow the shaft to be manually shaped by the userintra-operatively. Alternatively, malleable tubing may be used toconstruct the elongate shaft to allow manual shaping of the shaft.Additionally, when the distal end of the elongate shaft is curved towardthe cutting window, visibility of the cutting window location isimproved.

In certain variations, the elongate shaft may be flexible and asemi-rigid or rigid outer cannula or sheath may be provided on the shaftto change the radius of curvature on the shaft in a range fromsubstantially straight to curved, in an arc of about 180 degrees. Thecannula allows the operator to optimize the curvature of the shaft basedon the patient anatomy. The operator may also increase or decrease theforce between the elongate shaft or cutter and the target tissue beingcut by extending or retracting the cannula to increase or decrease thenatural radius of curvature of the elongate shaft.

In certain variations, a semi-rigid or rigid outer sheath or cannulapositioned over a flexible curved elongate shaft may be used to changethe radius of curvature of the curved shaft. The radius of curvature mayincrease when the straight and rigid sheath is extended over the curvedportion of the shaft, whereas the radius of curvature returns to itsprecurved or predetermined shape when retracted from the curved portionof the shaft.

The radius of curvature of a flexible curved elongate shaft may bealtered in-vivo by utilizing or advancing or retracting a cannula overthe elongate shaft. This allows the operator to change the radius ofcurvature of the elongate shaft in situ to gain access to a variety ofanatomical locations without removing the device or elongate shaft fromthe operative site to change the radius of curvature.

In certain variations, the distal tip of the elongate shaft may berounded and less likely to perforate sensitive structures or othertissue during advancement to a target tissue or while cutting is beingperformed. This reduces susceptibility to inadvertent contact withtissues that may result in unintended injury to the patient.

Reciprocating a cutter in a back-and-forth motion may shave and cuttissue by scissoring it rather than grabbing and ripping tissue as maybe the case with certain rotary cutters or rotary mechanisms or motors.Back-and-forth cutting action may shave tissue with less movement of thetissue, which reduces the tension on the tissue and consequent trauma tothe tissue thereby reducing the likelihood of bleeding. The excisedtissue may then be evacuated through an evacuation shaft and into atissue collection chamber.

An elongate shaft that includes a cutter shaft or an evacuation shaftwith a cutter at its distal end, which may be reciprocated in a back andforth motion along the longitudinal axis of the elongate shaft, may bepositioned in line or at an angle relative to the vacuum drivenmechanism or motor and the handle or chamber in which the mechanism ormotor is positioned. Positioning at an angle allows the device handle tobe positioned away from the control surfaces, light cord, and any powercables for an endoscope and/or camera that may also be used during thetissue cutting procedure. The operator's ease-of-use is improved becausethe endoscope and the cutting device are not interfering with oneanother.

A cutting device having a handle or hand piece that may be positioned inline with an elongate shaft or at an angle to the longitudinal axis ofthe elongate shaft may provide improved ergonomic features for theoperator. For example, when the operator is using a second device,(e.g., an endoscope as described supra) through the same orifice or portthat the elongate shaft of the cutting device has entered, the twodevices may interfere with one another. However, by positioning thehandle or hand piece at an angle to the longitudinal axis of the shaft,the top and sides of the cutting device around the shaft and theconnection between the handle and the shaft are at a very low profile.Thus, the likelihood of interference is reduced. In certain variations,the elongate shaft may be actuatable, such that the elongate shaft maybe moved between a position in line with a handle or at an angle to ahandle.

The back and forth reciprocating motion of a cutter shaft or anevacuation shaft with a cutter blade at its distal end may be translatedalong a nonlinear path. Therefore, it is possible to position the vacuumdriven mechanism or motor at an angle relative to elongate shaft of thedevice. Furthermore, the back and forth reciprocating motion of thecutter shaft or an evacuation shaft allows the elongate shaft of thecutting device to be bent at the distal portion of the shaft (e.g.,where the shaft is malleable) to allow it to be shaped to access avariety of locations in the anatomy.

In certain variations, separate conduits may be provided between themechanism and evacuation lumen such that vacuum for evacuating tissue isnot interrupted by the mechanism function.

An anvil component may be located at the distal end of the elongateshaft. An extension (e.g., a “tail”) of the anvil may be providedproximal to the cutting window. The extension may improve flexibility ofthe shaft allowing the shaft to be malleable closer to the distal end ofthe shaft. The anvil and/or extension may maintain or provide a guidefor the evacuation shaft or the cutter shaft as it translates orreciprocates axially. In the absence of an extension, a longer anvilcomponent that may be rigid over its entire length or a portion of itslength may be provided.

In certain variations, a cutting opening or window may be positioned onthe side of the elongate shaft. The side positioning allows the operatorto maintain visual contact or visualization on the position of theopening or window and tissue that comes into contact with the opening orwindow. This visual contact reduces the likelihood of unintentionallycausing injury to tissue.

A cutting window may be shaped to prevent the cutter from exiting thelumen of the elongate shaft or the anvil component, through the cuttingwindow. The cutting window in combination with the cutter may provide atissue scissoring cutting action, as compared to a guillotine cuttingaction on a straight sided cutting window.

In certain variations, the distal portion of an elongate shaft may beplastic, an indwelling anvil component may be metal, a cutter may bemetal and the evacuation tube may be plastic. This arrangement mayreduce the likelihood of heat build up from friction between movingand/or stationary components of the cutting device. This arrangement maycreate a scissoring cutting action, and/or allow the distal end of theelongate shaft to be flexible and malleable. Additionally, the use ofplastic components reduces or eliminates the possibility that electricalenergy may be unintentionally transmitted through the shaft therebyinjuring the patient.

Optionally, the elongate shaft may be rotatable about the axis of theshaft relative to the device handle or chamber, which allows theoperator to rotate the shaft without rotating the device handle.

In certain variations, one or more lumens 51, e.g., nonconcentric lumensmay be positioned in the elongate shaft (As shown in FIG. 1F).Nonconcentric lumens may provide advantages compared to single lumenshafts and shafts having concentric lumens. For example, one or more ofthe lumens may be used for the following purposes: to provide a fluidconduit for irrigant; to hold or contain one or more malleable wire(s)to maintain the shaft curvature when shaped by the operator; to containthe evacuation shaft or cutter shaft and evacuation lumen; and/or totransmit fluid to treat bleeding.

In certain variations, an evacuation lumen may be non contiguous aroundits circumference down a portion or the entire length of the evacuationshaft to improve flexibility while reducing the likelihood of kinkingthe evacuation lumen.

A small gap or a sealing O-ring between the evacuation shaft and theinside of the main lumen of the elongate shaft, may reduce thelikelihood of leakage of suction through the proximal end of theelongate shaft, which would reduce the suction present at the window.

Optionally, a ring of material may be provided between the outsidediameter of a noncontiguous evacuation lumen and the inside diameter ofa multi-lumen evacuation shaft or tubing that seals the air gap betweenthe two structures and thereby reduces leakage of air flow in the distaldirection from the device handle to the opening in the evacuation shaftor lumen, located proximal to the cutting window or opening.

Optionally, various fluids may be applied or delivered to the distal endof the elongate shaft where the cutter and window are positioned. Afluid may be emitted, via a lumen in the elongate shaft, from the distalend of an elongate shaft at a temperature that is low enough such thatthe fluid can be used as a bleeding therapy. A collagen foam may beemitted from the distal end of the elongate shaft as a bleeding therapy.These are inexpensive, quick, and easy ways to apply a bleeding therapyor anticoagulant to a bleeding site where tissue is being cut.Anti-coagulant substances emitted from the distal end of the elongateshaft as a bleeding therapy may be applied directly and conveniently tothe tissue, e.g., without exchanging or removing the cutting device toreplace it with a separate device intended for applying anticoagulationtherapy.

In certain variations, separate fluid conduit paths to the vacuum sourcemay be provided to allow the vacuum powered mechanism and cutter to beoperated independently from the tissue evacuation. The independent fluidpaths and operation capability of the vacuum powered mechanism andevacuation may allow the opening in the distal end of the elongate shaftof the cutting device to operate as a suction port to evacuate tissueand blood even when the vacuum powered mechanism is not in operation oris stalled or halted, e.g., when the trigger is actuated to engage andhold the shuttle piston to prevent its reciprocation.

Optionally, a single fluid conduit path between a cutting window and thevacuum source that includes an evacuation shaft and vacuum mechanism maybe utilized to reduce the air flow requirements of the device by usingair flow created by the vacuum to power both the vacuum mechanism andthe evacuation of tissue.

Set forth below are additional features or functions that may beutilized or included with various cutting devices described herein:

A clear tissue collection chamber may be utilized to allow the operatorto intraoperatively visualize resected tissue in real time.Additionally, the operator and patient are able to see whether thedevice has been previously used by inspecting the tissue collectionchamber.

A dual chamber tissue collection system may be provided to separatetissue resected from different locations in the event it is desired tobiopsy the tissue from two different locations in the body

A bi-stable switch fabricated from plastic, metal or other material andan elastic spring may be utilized in a mechanism to ensure reliabletransition of a Shuttle piston past a vacuum supply port to preventunstable flutter of the Shuttle piston and consequent mechanism or motorstall. Optionally, a bi-stable switch fabricated using sheet metal withtwo legs that are connected at one end but separated at the opposite endin their natural state may be provided. The separate sheet metal legsare then riveted or otherwise connected to create a bowed sheet metalcomponent that is stressed and bi-stable. Optionally, the separated endmay be folded and joined to result in a three dimensional curve that isstable in two positions. These variations may not require a separateelastic spring to be bi-stable.

Optionally, back-and-forth reciprocating motion from a vacuum poweredmechanism may be mechanically converted to rotational motion or rotaryoscillation to provide rotational or rotary oscillation mechanicaloutput by the mechanism.

A tissue evacuation shaft may be routed through the center of the drivePiston to provide an efficient method of transferring the mechanicaloutput of the mechanism to the cutter at the window.

To prevent vacuum leakage in the motor, a thin plastic seal may bemolded integral to a component and plastically deformed by squeezing thethin plastic seal in a die to increase its flexibility andconformability. This may reduce the cost of components and assemblylabor, and it may improve the overall reliability of the mechanism.Optionally, flash formed at a parting line of a mold may be used as aseal because it is very thin and flexible and conforms to the geometryof mating components while maintaining minimal friction betweencomponents. An O-ring may optionally be used to create a seal betweenmolded components.

In certain variations, a mechanism may include a Shuttle pistonpositioned or arranged adjacent to and/or parallel to the drive Pistonsuch that overall mechanism and or device size is reduced, the transferof mechanical motion between the pistons is easier and more efficientand the flow of air through the device is more efficient. Thisarrangement may allow for a smaller, easy to hold and use device. Theshuttle and drive piston's may be coupled by a bi-stable switch.

A spring-loaded Trigger may directly or indirectly interact with theShuttle piston or valve to turn the mechanism “ON” and “OFF.” Thisreliably and consistently controls the mechanism function. The triggermay be designed to always stop the motor with the Cutter shaft proximalto the opening or cutting window thereby leaving the cutting window opensuch that the device may be used in “suction only” mode through thewindow. Additionally, a device cleaning tool, such as a declogger, maybe threaded through the cutting window and proximally advanced throughand/or along the tissue evacuation path to clear or remove obstructionsin the tissue evacuation path.

A loop of flexible tubing that connects the evacuation shaft to astationary connection on the device, such as a vacuum port, provides alow cost way to allow back-and-forth motion of the evacuation shaft andthe mechanism without causing shaking, vibration or external motion ofother tubing or components in a chamber or handle, and withoutdislodging the evacuation path connection to the tissue collectionchamber. The loop of tubing may change shape to accommodate theback-and-forth motion of the evacuation shaft.

The cutting device may be designed such that irrigant does not flowunless suction is present at the opening or cutting window to draw theirrigant, e.g., to provide a self regulating supply of irrigant. Thismay be possible by supplying a reservoir of irrigant that is notpressurized relative to atmospheric air, however, when suction isapplied to the reservoir, irrigant flows from the reservoir and towardthe source of vacuum. An example of this is a syringe filled withirrigant that is connected to tubing; when suction is applied to thetubing, irrigant flows from the syringe and through the tubing towardthe source of vacuum. This will ensure the irrigant does notunintentionally flow out of the device and leak into the patient whereit may be problematic such as when aspirated by the patient (e.g., whenthe device is used in the respiratory passages), e.g., where a patientis under general anesthesia and can't communicate. An irrigant reservoirmay be located within the handle of the device such that it may befilled by the operator as needed, thereby reducing the number of tubesand connections that are tethered to the cutting device.

A cutting device or microdebrider having a reciprocating orback-and-forth cutting motion may optionally be powered by an integratedsupply of compressed air such as a CO2 cartridge or by a battery, e.g.,one that supplies electricity to a DC motor that actuates a cutter. Thiswould allow the vacuum supply to be used entirely to draw tissue intothe cutting window and to evacuate excised tissue thereby increasing orimproving a resection rate. A separate power console is not necessary toprovide power to the device.

Exemplary Vacuum Powered Mechanisms Or Motors

A vacuum powered or driven mechanism or motor used in various of thecutting devices described herein may be so called because it usessuction from an internal or external vacuum source to produce movement.The vacuum mechanism or motor does not create suction and is not to beconfused with a vacuum pump. The Vacuum is used to power a mechanism topower a medical device which cuts and evacuates tissue. A vacuum-poweredmechanism generates the reciprocating or rotating motion of the cutterin the device. The mechanism may be powered by the difference in ambientatmospheric air pressure on one side of a piston and a vacuum (orpartial vacuum) on the opposite side of the piston in the chamber orcylinder in which the piston is positioned.

One vacuum mechanism or motor described herein may be referred to as adouble action vacuum powered mechanism or double action mechanismbecause it uses suction to move the piston in both directions. Vacuum orsuction is alternately applied to either sides of a piston to cause thepiston to alternately move back and forth in the direction of the vacuum(or partial vacuum). Vacuum mechanisms or motors that use a spring toreturn them to their starting position may be referred to as a springaction or spring return mechanism. A single action mechanism or motormay use a vacuum to drive the piston in a single direction until thevacuum is vented and the piston is returned to its starting position bya spring.

One advantage of using vacuum to move the piston in both directions, ascompared to using a spring to return the piston to its startingposition, is that the efficiency of the motor is nearly doubled. Aspring return mechanism must have a piston size and cylinder volume thatis large enough to generate adequate force both to perform the workoutput required of the motor as well as to compress the return spring.The smaller piston size of a double action mechanism allows themechanism to be incorporated into a handheld device. The spring on aspring-return motor must be adequately sized to reliably return thepiston to its starting position with an adequate safety margin toreliably overcome friction and external forces on the mechanism.

Exemplary variations of vacuum driven mechanisms are described herein.FIGS. 3A-5B show various mechanisms in distal and proximal positions.The distal position refers to a piston in the mechanism being motivatedin a direction toward the distal end of the cutting device in which themechanism would be situated. Regarding the figures described below, froma viewer's perspective, the left side of the figures is the proximalside and the right side of the figures is the distal side. The proximalposition refers to a piston in the mechanism being motivated in adirection toward the proximal end of the cutting device in which themechanism would be situated.

FIG. 3A shows a cross sectional view of a variation of a double actionvacuum powered mechanism 310 or motor, similar to the mechanism 30,referred to above. The mechanism 310 includes a bi-stable switch. FIG.3A shows the mechanism 10 in a proximal position, while FIG. 3B showsthe double action vacuum powered mechanism in the distal position.

Referring to FIGS. 3A-3B, the vacuum powered mechanism 310 includes adrive piston 301 having a piston shaft 302. The drive piston 301including at least a portion of the piston shaft 302 are positionedwithin a drive piston chamber 307. The drive piston 301 divides orseparates the drive piston chamber into a proximal drive piston chamber307 a and a distal drive piston chamber 307 b. The drive piston 301 mayreciprocate proximally and distally within the drive piston chamber 307when vacuum and ambient air are alternately applied to opposite sides ofthe drive piston 1 in drive piston chambers 307 a and/or 307 b. Thepiston shaft 302 may reciprocate along with the drive piston 301, andthe reciprocating piston shaft 302 may conduct reciprocating motionoutput.

A bi-stable switch 303 is connected or coupled to a shuttle piston 314and a switch spring 305. The switch spring 305 may cause the bi-stableswitch 303 to quickly transition from a distal position to a proximalposition and vice versa. The bi-stable switch is stable when it is ineither a proximal position (FIG. 3A) or a distal position (FIG. 3B), butnot when it is in between those two positions and therefore the switchresists residence in an in-between state. As a result, the mechanismdoes not “flutter” or the mechanism minimizes “flutter” when intransition between states. For example, the shuttle valve 313 may notflutter or not fail to fully transition from a proximal to a distalposition or vice versa as the bi-stable switch causes the shuttle piston314 and a shuttle valve 313 to transition or translate in the proximalor distal direction over and past a shuttle chamber vacuum supply port308.

The bi-stable switch 303 may be actuated by the drive piston shaft 302when the drive piston 1, and therefore the piston shaft 302, move ineither the proximal or distal directions. Actuation of the bi-stableswitch 303 results in movement of the shuttle piston 314 in either theproximal or distal directions. Movement of the drive piston in theproximal direction results in movement of the shuttle piston in theproximal direction via the bi-stable switch, while movement of the drivepiston in the distal direction results in movement of the shuttle pistonin the distal direction via the bi-stable switch.

The shuttle piston 314 is positioned within a shuttle piston chamber.The shuttle piston 314 includes a shuttle valve 313 or flange which mayextend radially therefrom, which separates or divides the shuttle pistonchamber into a proximal shuttle piston chamber 315 and a distal shuttlepiston chamber 316. Proximal shuttle piston chamber 315 may be in fluidcommunication with proximal drive piston chamber 307 a via proximalvacuum slot 304. Distal shuttle piston chamber 316 may be in fluidcommunication with distal drive piston chamber 307 b via distal vacuumslot 306.

The shuttle piston (314) may also include a proximal ambient air seal(309), a proximal cruciform (310), a distal ambient air seal (311), adistal cruciform (312), and a central shaft connecting the abovecomponents.

A shuttle piston chamber vacuum supply port (308) may be connected to anexternal or internal vacuum source or supply to evacuate the proximalshuttle piston chamber 315 and/or the distal shuttle piston chamber 316.The vacuum port 308 may allow for evacuation by vacuum of the proximaldrive piston chamber 307 a via the proximal vacuum slot 304 and theproximal shuttle piston chamber 315. The vacuum port 308 may allow forevacuation by vacuum of the distal drive piston chamber 307 b via thedistal vacuum slot 306 and the distal shuttle piston chamber 316.

For example, Proximal drive piston Chamber (307 a) may be evacuated byvacuum when in fluid communication with the external vacuum source viathe Vacuum Port (308), Proximal Shuttle piston Chamber (315), andproximal vacuum slot 304. Distal drive piston Chamber (307 b) may beevacuated by vacuum when in communication with the external vacuumsource via the Vacuum Port (308), Distal Shuttle piston Chamber (316),and distal vacuum slot 306. Presence of vacuum in Proximal drive pistonChamber 307 a results in differential pressure between the proximal anddistal sides of the Piston (301) that results in working force to movethe Piston (301) proximally when ambient air is in the distal drivepiston Chamber (307 b). Alternately, ambient air (322) in proximal drivepiston Chamber 307 a applies working force to move the Piston (301)distally when the Distal drive piston Chamber (307 b) is evacuated.

The shuttle piston 314 may be translated or positioned in a shuttlepiston chamber such that Shuttle piston valve 313 can seal against theshuttle block (321) to the distal side of the vacuum port (308) to allowthe proximal shuttle piston chamber (315) and/or proximal drive pistonchamber (307 a) to be evacuated by communicating with an external vacuumsupply. Alternatively, the shuttle piston 314 may be translated orpositioned in a shuttle piston chamber such that the shuttle pistonvalve 313 may seal against the shuttle block (321) to the proximal sideof the vacuum port (308) to allow the distal shuttle piston chamber(316) and/or distal drive piston chamber (307 b) to be evacuated bycommunicating with the external vacuum supply.

The proximal shuttle piston chamber (315) may allow for fluidcommunication between the Vacuum Port (308) and the Proximal drivepiston Chamber (307 a) through the Proximal Vacuum Slot (304). Theproximal shuttle piston chamber (3315) may also allow for fluidcommunication between the Proximal drive piston Chamber 307 a andambient air when the Proximal Shuttle Seal (309) is in the proximalposition, i.e., an open or unsealed position.

The Distal Shuttle piston Chamber (316) may allow for fluidcommunication between the Vacuum Port (308) and the Distal drive pistonChamber (307 b) through the Distal Vacuum Slot (306). The Distal Shuttlepiston Chamber (316) may allow for fluid communication between theDistal drive piston Chamber 307 b and ambient air when the DistalShuttle Seal 311 is in the distal position, i.e., an open or unsealedposition.

The proximal ambient air seal (309) of the shuttle piston 314 may sealagainst shuttle block (321) to prevent ambient air leakage into proximalshuttle piston chamber 315 when the proximal shuttle piston chamber(315) is evacuated. Also, the proximal cruciform (310) can maintainshuttle piston (314) position concentricity relative to proximal shuttlepiston chamber (315), e.g., when the shuttle piston (314) moves to aproximal position and vents ambient air to the proximal shuttle pistonchamber (315).

The distal ambient air seal (311) of the shuttle piston 314 may sealagainst shuttle block (321) to prevent ambient air leakage into distalshuttle piston chamber 316 when the distal shuttle piston chamber (316)is evacuated. Also, the distal cruciform (312) can maintain shuttlepiston (314) position concentricity relative to distal shuttle pistonchamber (316), e.g., when the shuttle piston (314) moves to a distalposition and vents ambient air to the distal shuttle piston chamber(316).

The vacuum powered mechanism 310 may also include a Distal drive pistonchamber Endcap (317), which may prevent or minimize fluid communicationbetween ambient air and the Distal drive piston Chamber (307 b) inaddition to providing a sealing and bearing surface with the drivePiston Shaft (302). The vacuum powered mechanism 310 may also include aDistal drive piston chamber Endcap Seal (318), which may prevent orminimize ambient air leakage between the Distal drive piston chamberEndcap (317) and the drive piston Shaft (302), e.g., when the Distaldrive piston Chamber (307 b) is evacuated.

The vacuum powered mechanism 310 may also include a Proximal drivepiston Chamber Endcap (319), which may prevent or minimize fluidcommunication between ambient air and the Proximal drive piston Chamber(37 a) in addition to providing a sealing and bearing surface with thedrive Piston Shaft (302). The vacuum powered mechanism or motor 310 mayalso include a Proximal drive piston Chamber Endcap Seal (320), whichmay prevent or minimize ambient air leakage between the Proximal drivepiston Chamber Endcap (319) and the drive Piston Shaft (302), e.g., whenthe Proximal drive piston Chamber (307 a) is evacuated.

The drive piston shaft 302 may seal against the endplates or endcaps317, 319 or shuttle block 321 to prevent or minimize loss of vacuum toambient air 322. Also, various seals known to person of skill in the artmay be utilized to seal the piston shaft against the endplates orendcaps 317, 319 or shuttle block 321.

A shuttle block 321 or other frame, structure, or casing may provide anouter structure for the vacuum powered mechanism 310. Ambient air 322refers to air at atmospheric pressure which is located outside of thevacuum mechanism. Ambient air 322 may also be allowed to flow insidevarious chambers of the vacuum powered mechanism during use of themechanism as described herein.

In use or in operation, the vacuum powered mechanism 310 operates by apneumatic mechanism, method or logic that utilizes an external orinternal vacuum source to provide the force to cause reciprocatingmotion of the drive piston 301 in both proximal and distal directions. Abi-stable switch may be utilized to transition the mechanism as itreverses or changes direction.

For example, the vacuum port 308 may be opened to the distal drivepiston chamber 307 b to evacuate the distal drive piston chamber 307 band ambient air is closed to the distal drive piston chamber 307 b,while ambient air is opened to the proximal drive piston chamber 307 aand the vacuum port is closed to the proximal drive piston chamber 307b. The drive Piston advances toward a distal position due to the vacuuminside the distal drive piston chamber 307 b, on the distal side of thedrive piston 301 and the ambient air pressure in the proximal cylinderchamber, on the proximal side of the drive piston 301.

As a result of the differential pressure created on opposite sides ofthe drive piston 301, the drive piston Rod or shaft 302 moves throughits dwell until it contacts the bi-stable switch 303, causing thebi-stable switch 303 to rapidly change states from a proximal positionto distal position, moving in the distal direction. The bi-stable switchis attached to the shuttle piston 314 and rapidly causes the shuttle 314to move from a proximal position to distal position in the shuttlechamber. As a result, the vacuum seal 313 on the shuttle piston 314moves from the proximal side of vacuum port 308 to the distal side ofthe vacuum port 308, opening the vacuum port 308 to the proximal drivepiston chamber 307 a to evacuate the proximal drive piston chamber 307a, and closing the vacuum port 308 to the distal drive piston chamber307 b. Also, the distal seal 311 on the shuttle piston 314 opens theambient air 322 to vent the distal drive piston chamber 307 b to ambientpressure, and the proximal seal 309 on the shuttle piston 314 closes theambient air vent to the proximal drive piston chamber 307 a.

The drive piston 301 then reverses direction and moves in the proximaldirection, due to the vacuum inside the proximal drive piston chamber307 a, on the proximal side of the drive piston and the ambient airpressure in the distal drive piston chamber, on the distal side of thedrive piston 301.

As a result of the differential pressure created on opposite sides ofthe drive piston 301, drive piston Rod or shaft 302 moves through itsdwell until it contacts the bi-stable Switch, causing the bi-stableswitch to rapidly change states from a distal position to a proximalposition. The bi-stable switch is attached to the Shuttle 314 andrapidly causes the Shuttle 314 to move from its distal position to aproximal position in the shuttle chamber. As a result, the vacuum seal313 on the shuttle piston 314 moves from the distal side of the VacuumPort 308 to the proximal side of the vacuum port 308, opening the vacuumport 308 to the distal drive piston chamber 307 b to evacuate the distaldrive piston chamber 307 b, and closing the vacuum port 308 to theproximal drive piston chamber 307 a. Also, the Proximal Seal 309 on theShuttle piston 314 opens the ambient air 322 to vent the proximal drivepiston chamber 307 a to ambient pressure, and the Distal Seal 311 on theShuttle piston 314 closes the ambient air vent to the distal drivepiston chamber 307 b.

Consequently, the mechanism has completed one cycle and is free tocontinue reciprocating as described above by alternating suction or airpressure on opposite sides of the piston, as long as adequate vacuum isavailable to the mechanism. Indeed, the above Steps may repeat asnecessary such that the vacuum powered mechanism creates a reciprocatingmotion until the vacuum source is disconnected, turned off, or if thevacuum is inadequate to overcome the force required to move the drivepiston 301 or if the mechanism 310 is stalled or stopped.

The reciprocating motion of the mechanism may be utilized to actuate acutting device or to operate or actuate another device, e.g., anothermedical device. In certain variations, cutting device may be positionedby maneuvering a flexible or malleable shaft of the device e.g.,manually or automatically. The shaft may be maneuvered or positionedaround sensitive tissues or structures in the human body by changing theshape of the shaft. For example, extending or retracting an outer sheathor cannula on the shaft or advancing or retracting the shaft relative tothe outer sheath, thereby allowing improved maneuverability of the shaftaround structures or within confined spaces may be performed, e.g.,allowing a shaft's predetermined curvature to position the distal end ofthe shaft near a target site. Such mechanisms, techniques and devicesinclude those described in U.S. patent application Ser. Nos. 11/848,565,11/848,564, and 11/848,562, each of which is incorporated herein byreference in their entirety for all purposes.

FIG. 4A shows a cross sectional view of another variation of a doubleaction vacuum powered mechanism or motor in a proximal position, whileFIG. 4B shows the double action vacuum powered mechanism or motor in adistal position.

Referring to FIG. 4A-4B, the vacuum powered mechanism 430 includes apiston 431 having a piston shaft 432. The piston 431 including at leasta portion of the piston shaft 432 are positioned within a cylinderchamber 437. The piston 431 divides or separates the cylinder chamber437 into a proximal cylinder chamber 437 a and a distal cylinder chamber437 b. The piston 431 may reciprocate proximally and distally within thecylinder chamber 437 when vacuum and ambient air are alternately appliedto opposite sides of the piston 431 in cylinder chambers 437 a and/or437 b. The piston 431 and piston shaft 432 may reciprocate, and thereciprocating piston shaft 432 may conduct reciprocating motion output.

A proximal shuttle pin 433 is connected to a shuttle 444. The shuttlepin 433 may be actuated by the piston 431 when the piston 431 moves inthe proximal direction and contacts the proximal shuttle pin 433.Actuation of the proximal shuttle pin 433 by the piston results inmovement of the shuttle 444 in the proximal direction.

A distal shuttle pin 435 is also connected to the shuttle 444. Thedistal shuttle pin 435 may be actuated by the piston 431 when the piston431 moves in the distal direction and contacts the distal shuttle pin435. Actuation of the distal shuttle pin 435 by the piston results inmovement of the shuttle 444 in the distal direction. Indeed, movement ofthe piston in the proximal direction results in movement of the shuttlein the proximal direction via contact with the proximal shuttle pin 433,while movement of the piston in the distal direction results in movementof the shuttle in the distal direction via contact with the distalshuttle pin 435.

The shuttle 444 is positioned within a shuttle chamber. The shuttle 444includes a shuttle valve 443 or flange which may extend radiallytherefrom, which separates or divides the shuttle chamber into aproximal shuttle chamber 445 and a distal shuttle chamber 446.

Proximal shuttle chamber 445 may be in fluid communication with proximalcylinder chamber 437 a via proximal shuttle pin slot 434. Proximalshuttle pin slot 434 also provides an opening in which the proximalshuttle pin 433 may translate between proximal and distal positions.Distal shuttle chamber 446 may be in fluid communication with distalcylinder chamber 437 b via distal shuttle pin slot 436. Distal shuttlepin slot 436 also provides an opening in which the distal shuttle pin435 may translate between proximal and distal positions.

The shuttle (444) may also include a proximal ambient air seal (439), aproximal cruciform (440), a distal ambient air seal (441), a distalcruciform (442), and a central shaft connecting the above components.

A vacuum port (438) may be connected to an external or internal vacuumsource or supply to evacuate the proximal shuttle chamber 445 and thedistal shuttle chamber 446. The vacuum port 438 may allow for evacuationby vacuum of the proximal cylinder chamber 437 a via the proximalshuttle pin slot 434 and the proximal shuttle chamber 445. The vacuumport may allow for evacuation by vacuum of the distal cylinder chamber437 b via the distal shuttle pin slot 436 and the distal shuttle chamber446.

For example, Proximal Cylinder Chamber (437 a) may be evacuated byvacuum when in fluid communication with the external vacuum source viathe Vacuum Port (438), Proximal Shuttle Chamber (445), and ProximalShuttle Pin Slot 434. Distal Cylinder Chamber (437 b) may be evacuatedby vacuum when in communication with the external vacuum source via theVacuum Port (438), Distal Shuttle Chamber (446), and Distal Shuttle PinSlot (436). Presence of vacuum in Proximal Cylinder Chamber 437 aresults in differential pressure between the proximal and distal sidesof the Piston (431) that results in working force to move the Piston(431) proximally when ambient air is in the distal Cylinder Chamber (437b). Alternately, ambient air (422) in proximal Cylinder Chamber 437 aapplies working force to move the Piston (431) distally when the DistalCylinder Chamber (437 b) is evacuated.

The shuttle 44 may be translated or positioned in a shuttle chamber suchthat Shuttle valve 443 can seal against the shuttle block (451) to thedistal side of the vacuum port (438) to allow the proximal shuttlechamber (445) and proximal cylinder chamber (437 a) to be evacuated bycommunicating with an external vacuum supply. Alternatively, the shuttle444 may be translated or positioned in a shuttle chamber such that theshuttle valve 443 may seal against the shuttle block (451) to theproximal side of the vacuum port (438) to allow the distal shuttlechamber (446) and distal cylinder chamber (437 b) to be evacuated bycommunicating with the external vacuum supply.

The proximal shuttle chamber (445) may allow for fluid communicationbetween the Vacuum Port (438) and the Proximal Cylinder Chamber (437 a)through the Proximal shuttle pin Slot (434). The proximal shuttlechamber (445) may also allow for fluid communication between theProximal Cylinder Chamber 437 a and ambient air when the ProximalShuttle Seal (439) is in the proximal position, i.e., an open orunsealed position.

The Distal Shuttle Chamber (446) may allow for fluid communicationbetween the Vacuum Port (438) and the Distal Cylinder Chamber (437 b)through the Distal shuttle pin Slot (436). The Distal Shuttle Chamber(446) may allow for fluid communication between the Distal CylinderChamber 4376 and ambient air when the Distal Shuttle Seal 41 is in thedistal position, i.e., an open or unsealed position.

The proximal ambient air seal (439) of the shuttle 44 may seal againstshuttle block (421) to prevent ambient air leakage into proximal shuttlechamber 445 when the proximal shuttle chamber (445) is evacuated. Also,the proximal cruciform (440) can maintain shuttle (444) positionconcentricity relative to proximal shuttle chamber (445), e.g., when theshuttle (444) moves to a proximal position and vents ambient air to theproximal shuttle chamber (445).

The distal ambient air seal (441) of the shuttle 444 may seal againstshuttle block (51) to prevent ambient air leakage into distal shuttlechamber 446 when the distal shuttle chamber (446) is evacuated. Also,the distal cruciform (442) can maintain shuttle (444) positionconcentricity relative to distal shuttle chamber (446), e.g., when theshuttle (444) moves to a distal position and vents ambient air to thedistal shuttle chamber (446).

The vacuum powered mechanism 430 may also include a Distal CylinderEndcap (447), which may prevent or minimize fluid communication betweenambient air and the Distal Cylinder Chamber (437 b) in addition toproviding a sealing and bearing surface with the Piston Shaft (432). Thevacuum powered mechanism 430 may also include a Distal Cylinder EndcapSeal (448), which may prevent or minimize ambient air leakage betweenthe Distal Cylinder Endcap (447) and the Piston Shaft (432), e.g., whenthe Distal Cylinder Chamber (437 b) is evacuated.

The vacuum powered mechanism 430 may also include a Proximal CylinderEndcap (449), which may prevent or minimize fluid communication betweenambient air and the Proximal Cylinder Chamber (437 a) in addition toproviding a sealing and bearing surface with the Piston Shaft (432). Thevacuum powered mechanism 430 may also include a Proximal Cylinder EndcapSeal (450), which may prevent or minimize ambient air leakage betweenthe Proximal Cylinder Endcap (449) and the Piston Shaft (432), e.g.,when the Proximal Cylinder Chamber (437 a) is evacuated.

The piston shaft 432 may seal against the endplates or endcaps 447, 449or shuttle block 451 to prevent or minimize loss of vacuum to ambientair 422. Also, various seals known to person of skill in the art may beutilized to seal the piston shaft against the endplates or endcaps 447,449 or shuttle block 451.

A shuttle block 451 or other frame, structure, or casing may provide anouter structure for the vacuum powered mechanism 430. Ambient air 422refers to air at atmospheric pressure which is located outside of thevacuum powered mechanism. Ambient air 422 may also be allowed to flowinside various chambers of the vacuum powered mechanism during use ofthe mechanism as described herein.

In use or in operation, the vacuum powered mechanism 430 operates by apneumatic mechanism, method or logic that does not require inertial massto move the mechanism through transition (such as a flywheel) and thatuses an external or internal vacuum source to provide the force to causereciprocating motion of the piston 31 in both proximal and distaldirections.

For example, the vacuum port 438 may be opened to the distal cylinderchamber 437 b to evacuate the distal cylinder chamber 437 b and ambientair is closed to the distal cylinder chamber 37 b, while ambient air isopened to the proximal cylinder chamber 437 a and the vacuum port isclosed to the proximal cylinder chamber 437 b. The Piston advancestoward a distal position due to the vacuum inside the distal cylinderchamber 437 b, on the distal side of the piston 431 and the ambient airpressure in the proximal cylinder chamber, on the proximal side of thepiston 431.

As a result of the differential pressure created on opposite sides ofthe piston 431, the Piston 431 moves through the chamber and contactsthe distal shuttle pin 435, causing the shuttle 444 to move from aproximal position to distal position in the shuttle chamber. As aresult, the vacuum seal 443 on the shuttle 444 moves from the proximalside of vacuum port 438 to the distal side of the vacuum port 38,opening the vacuum port 438 to the proximal cylinder chamber 437 a toevacuate the proximal cylinder chamber 437 a, and closing the vacuumport 438 to the distal cylinder chamber 437 b. Also, the distal seal 441on the shuttle 444 opens the ambient air 422 to vent the distal cylinderchamber 437 b to ambient pressure, and the proximal seal 439 on theshuttle 444 closes the ambient air vent to the proximal cylinder chamber437 a.

It may be necessary to have adequate evacuated volume in the distalcylinder chamber 437 b to cause the Piston (431) to continue translatingdistally after the Shuttle Valve (443) shuts off vacuum from vacuum port438 to the distal cylinder chamber 437 b. This may ensure that theshuttle 444 continues to translate in the distal direction as a resultof the moving piston contacting the distal shuttle pin and therebymoving the shuttle 444, such that shuttle valve 443 completely passesvacuum port 438, shutting off the vacuum to the distal cylinder chamber437 b, in manner that avoids or minimizes valve flutter or unwantedfluctuation of the valve 443 between proximal and distal positions inthe shuttle chamber.

The piston 431 then reverses direction and moves in the proximaldirection, due to the vacuum inside the proximal cylinder chamber 437 a,on the proximal side of the Piston and the ambient air pressure in thedistal cylinder chamber 437 b, on the distal side of the piston 431.

As a result of the differential pressure created on opposite sides ofthe piston 431, the piston 431 moves through its dwell or the cylinderchamber and contacts the proximal shuttle pin 433, causing the Shuttle444 to move from its distal position to proximal position in the shuttlechamber. As a result, the vacuum seal 443 on the shuttle 444 moves fromthe distal side of the Vacuum Port 438 to the proximal side of thevacuum port 38, opening the vacuum port 438 to the distal cylinderchamber 37 b to evacuate the distal cylinder chamber 437 b, and closingthe vacuum port 38 to the proximal cylinder chamber 437 b. Also, theProximal Seal 439 on the Shuttle 444 opens the ambient air 422 to ventthe proximal Cylinder chamber 437 a to ambient pressure, and the DistalSeal 441 on the Shuttle 444 closes the ambient air vent to the distalcylinder chamber 437 b.

Again, it may be necessary to have adequate evacuated volume in theproximal cylinder chamber 437 a to cause the Piston (431) to continuetranslating proximally after the Shuttle Valve (443) shuts off vacuumfrom vacuum port 438 to the proximal cylinder chamber 437 a. This mayensure that the shuttle 444 continues to translate in the proximaldirection as a result of the moving piston contacting the proximalshuttle pin and thereby moving the shuttle 444, such that shuttle valve443 completely passes vacuum port 438, shutting off the vacuum to theproximal cylinder chamber 437 b, in manner that avoids or minimizesvalve flutter or unwanted fluctuation of the valve 443 between proximaland distal positions in the shuttle chamber.

Consequently, the mechanism has completed one cycle and is free tocontinue reciprocating as described above by alternating air pressure onopposite sides of the piston, as long as adequate vacuum is available tothe mechanism. Indeed, the above Steps may repeat as necessary such thatthe vacuum powered mechanism creates a reciprocating motion until thevacuum source is disconnected, turned off, or if the vacuum isinadequate to overcome the force required to move the Piston 431.

In certain variations of a vacuum powered mechanism, a vacuum may becreated in the “dead space” on the distal or proximal end of theCylinder that is adequate to cause the Piston to continue movingdistally or proximally after the external vacuum source is shut off fromthe Cylinder. The “dead space” volume in the proximal or distal end ofthe Cylinder serves as an “accumulator” that encourages the Piston tocontinue moving distally or proximally thereby eliminating the need formass to create inertia to move the valve through transitions from onestate to another.

In another variation, a method of reducing pneumatic valve instabilityor flutter caused by the valve or Shuttle attempting to move back andforth between states includes exposing one side of the shuttle valve tothe vacuum source and the opposite side of the shuttle valve to ambientair. This may cause the shuttle valve to move in the direction of thevacuum and will more fully open the port connecting the ambient air tothe Cylinder.

The reciprocating motion of the mechanism may be utilized to actuate acutting device or to operate or actuate another device, e.g., anothermedical device. In certain variations, cutting device may be positionedby maneuvering a flexible or malleable shaft of the device e.g.,manually or automatically. The shaft may be maneuvered or positionedaround sensitive tissues or structures in the human body by changing theshape of the shaft. For example, extending or retracting an outer sheathor cannula on the shaft or advancing or retracting the shaft relative tothe outer sheath, thereby allowing improved maneuverability of the shaftaround structures or within confined spaces may be performed, e.g.,allowing a shaft's predetermined curvature to position the distal end ofthe shaft near a target site. Such mechanisms, techniques and devicesinclude those described in U.S. patent application Ser. Nos. 11/848,565,11/848,564, and 11/848,562, each of which is incorporated herein byreference in their entirety for all purposes.

Further describing operations of a variation of a mechanism asillustrated in FIGS. 4A-4B, the shuttle 444 may start in the proximal ordistal positions. In certain variations, a small spring (not shown) maybe used to position the piston and/or the shuttle component in aparticular starting position.

FIG. 4A shows the shuttle 444 starting in the proximal position. Whenexternal vacuum is applied to the mechanism through the Vacuum Port(438), the Shuttle Valve (443) is on the proximal side of the VacuumPort (448) which results in evacuation of the air in the Distal CylinderChamber (437 b), the Distal Shuttle Pin Slot (436), and the DistalShuttle Chamber (446). Consequently, the differential pressure on theproximal and distal sides of the Piston (431) causes the piston to movedistally.

The vacuum may apply a force greater than the frictional forces actingon the Piston in addition to the forces required by the mechanism toperform work.

As the Piston (431) moves distally, it contacts the Distal Shuttle Pin(435) and moves the Shuttle (444) distally. As a result, the ShuttleValve (443) closes off the Vacuum Port (438) to the distal side of themechanism.

It may be necessary to have adequate evacuated volume on the distal sideof the chamber or in the distal cylinder chamber 437 b to cause thePiston (431) to continue translating distally after the Shuttle Valve(443) shuts off vacuum to the distal side of the mechanism or to thedistal cylinder chamber 437 b.

As the Shuttle (444) moves distally, the Distal Ambient Air Seal (441)opens to allow ambient air from outside of the mechanism to flow intothe distal side of the mechanism and fill the evacuated volume includingthe Distal Cylinder Chamber (437 b), the Distal Shuttle Pin Slot (436),and the Distal Shuttle Chamber (446). Additionally, the Proximal AmbientAir Seal (439) closes and the Shuttle Valve (443) opens the vacuum port438 to the proximal side of the mechanism and/or to the proximalcylinder chamber 437 a.

The Shuttle Valve (443) moves to the distal side of the Vacuum Port(438) which results in evacuation of the air in the Proximal CylinderChamber (437 a), the Proximal Shuttle Pin Slot (434), and the ProximalShuttle Chamber (445). Consequently, the differential pressure on theproximal and distal sides of the Piston (431) causes the piston to moveproximally.

As the Piston (431) moves proximally, it contacts the Proximal ShuttlePin (433), and moves the Shuttle (444) proximally. As a result, theShuttle Valve (443) closes off the Vacuum Port (438) to the proximalside of the mechanism or to the proximal cylinder chamber 437 a.

It may be necessary to have adequate evacuated volume on the proximalside of the chamber or in the proximal cylinder chamber 437 a to causethe Piston (431) to continue translating proximally after the ShuttleValve (443) shuts off vacuum to the proximal side of the mechanism or tothe proximal cylinder chamber 437 a.

As the Shuttle (444) moves proximally, the Proximal Ambient Air Seal(439) opens to allow ambient air from outside of the mechanism to flowinto the proximal side of the mechanism and fill the evacuated volumeincluding the Proximal Cylinder Chamber (437 a), the Proximal ShuttlePin Slot (434), and the Proximal Shuttle Chamber (445). Additionally,the Distal Ambient Air Seal (441) closes and the Shuttle Valve (443)opens the vacuum port 8 to the distal side of the mechanism and/or thedistal cylinder chamber 437 b.

The Shuttle Valve (443) is on the proximal side of the Vacuum Port (438)which results in the mechanism being returned to the starting positiondescribed above. Consequently, the mechanism has completed one cycle andis free to continue reciprocating as described above as long as adequatevacuum is available to the mechanism.

FIGS. 5A-5B show another variation of a vacuum powered mechanism 560 ormotor including a spring return mechanism. FIG. 5A shows the mechanismwith a Piston 561 in a starting or proximal position, and FIG. 5B showsthe mechanism with a Piston 561 in a distal position.

Referring to FIG. 5A-5B, the vacuum powered mechanism 560 includes apiston 561 having a piston shaft 62. The piston 561 including at least aportion of the piston shaft 562 are positioned within a cylinder chamber581. The piston 561 divides or separates the cylinder chamber 581 into aproximal cylinder chamber 581 a and a distal cylinder chamber 581 b. Thepiston 561 may reciprocate distally within the cylinder chamber 581 whenthe distal side of the piston 561 is evacuated or when distal cylinderchamber 581 b is evacuated. Ambient air may be or may always be presenton the proximal side of the piston 561 or in the proximal cylinderchamber 581 a. Cylinder chamber 581 a may be open to ambient air or mayalways be open to ambient air. The piston shaft 565 may reciprocatealong with the piston 561, and the reciprocating piston shaft 565 mayconduct reciprocating motion output. The piston shaft may serve totransmit the motion from the piston as the mechanism output.

A shuttle 562 may be connected to the Piston (561) and the shuttle 562may reciprocate along with the Piston 561. The shuttle 562 may bepositioned in a shuttle chamber. The shuttle includes a proximal sealflange 563 which may be integral to the shuttle 562 and/or extendradially therefrom. The seal flange 563 provides a seal between theAmbient Air Conduit (574) and the Distal Cylinder Chamber (581 b) whenthe Distal Cylinder Chamber (581 b) is evacuated. Proximal Seal Flange563 may also contact a Proximal Stop Pin (580) to stop the proximalmovement of the Shuttle (562).

The shuttle may also include a shuttle valve 564, which may be integralto the shuttle and/or may extend radially therefrom. The shuttle valve564 may separate or divide the shuttle chamber into a proximal shuttlechamber 588, on the proximal side of the valve 564, and a vacuum shuttlechamber 583 on the distal side of the valve 564. The Shuttle Valve 564provides a seal, which may seal, e.g., against the shuttle block 578, tothe distal or proximal side of the distal conduit 572. The shuttle valve564 may provide a seal to the proximal side of the distal conduit 572 toopen the distal conduit 572, and the distal cylinder chamber 581 b, to avacuum port 575 to allow the distal cylinder chamber 581 b to beevacuated by communicating with an external vacuum supply.

The shuttle valve 564 may also provide a seal to the distal side of thedistal conduit 572 to open the distal conduit 572, and the distalcylinder chamber 581 b, to an ambient air conduit 574 to allow thedistal cylinder chamber 581 b to be open to ambient air.

The piston shaft 565 may be integral to the piston 61 on the proximalend of the piston shaft 565 and integral to the distal piston shaft 570(i.e., the external portion of the piston shaft 565 located at thedistal end of the piston shaft 565. A Shuttle Return Surface (566) isIntegral to the Piston Shaft (565) and serves to contact the distal endof the Shuttle (562) to motivate it proximally when the Piston 561 andpiston shaft 565 are translating in the proximal direction.

The piston shaft 565 may also include a Distal Seal Flange (567), whichmay extend radially therefrom. The distal seal flange 567 may sealambient air in the return spring chamber 584, sealing off the returnspring chamber 584 from the shuttle vacuum chamber 583. The distal sealflange may also provide a surface for a Return Spring (568) to act uponto motivate or translate the Piston Shaft (565) proximally or in theproximal direction during a return stroke.

A Return Spring (568), is positioned in the return spring chamber 584and stores mechanical energy by compressing during the distal stroke ofthe mechanism, i.e., when the piston and piston shaft are moved in thedistal direction. The mechanical energy is released when the ReturnSpring 568 motivates the Piston Shaft 565 proximally during the returnstroke of the mechanism.

The mechanism 560 may include a Distal End Plate (569) which serves as adistal stop for the Return Spring (568).

The mechanism 560 may also include various conduits. A Proximal Conduit(571) may provide a connection or conduit for fluid communicationbetween the Distal Cylinder Chamber (581 b) and a Parallel Conduit(573). A Distal Conduit (572), as identified above, may provide aconnection or conduit for fluid communication between the ProximalShuttle Chamber (588) and the Parallel Conduit (573). The ParallelConduit (573) may provide a connection or conduit for fluidcommunication between the Proximal Conduit (571) and the Distal Conduit(572). The Ambient Air Conduit (574) may provide a conduit to allowambient air to vent proximal shuttle chamber 588 and Distal CylinderChamber (581 b) depending on the positioning of shuttle valve 564relative to the distal conduit 572.

The Vacuum Port (575) connects the mechanism to an external vacuumsource and evacuates shuttle vacuum chamber 583 and may evacuate distalcylinder chamber 581 b depending on the positioning of shuttle valve 564relative to the distal conduit 572.

The mechanism 560 may also include a Return Spring Vent (576) whichvents the Return Spring Chamber (584) to ambient air to maintain ambientair pressure in the Return Spring Chamber (584) as the chamber changesvolume due to compression and extension of the Return Spring (568). TheReturn spring chamber 84 contains the return spring 68. The returnspring chamber 84 may be or may always be at ambient pressure via thereturn spring vent 76.

A Distal Parallel Conduit (77) may also be provided. The distal parallelconduit 77 may be an Artifact from machining the mechanism Block (78)and the Distal Parallel Conduit 77 may be plugged at the distal endprior to use.

A mechanism block 578 or other frame, structure, or casing may providean outer structure for the vacuum powered mechanism 560. Ambient air 522refers to air at atmospheric pressure which is located outside of thevacuum powered mechanism. Ambient air 522 may also be allowed to flowinside various chambers of the vacuum powered mechanism during use ofthe mechanism as described herein.

A Distal Stop Pin (579) provides a distal stop for the Shuttle (562) bypreventing distal translation of the Shuttle (562) beyond the locationof the distal stop pin 579.

A Proximal Stop Pin and Ball Plunger (580) may provide a proximal stopfor the Shuttle (562) when in contact with the Proximal Seal Flange(563). The Ball Plunger provides normal force on the Shuttle to increasethe force required to translate the shuttle laterally thereby reducingor eliminating the likelihood of valve “flutter” or unwanted fluctuationof the valve 564 between proximal and distal positions in the shuttlechamber relative to distal conduit 572.

The Distal Cylinder Chamber (581 b) alternates between vacuum andambient pressure to motivate the Piston (561) distally when the DistalCylinder Chamber (581 b) is in vacuum and to allow the Return Spring(568) to motivate the Piston Shaft (562) and/or piston 61 proximallywhen the Distal Cylinder Chamber 581 b is at ambient pressure.

The Proximal Shuttle Chamber (588) may be at ambient pressure or mayalways be at ambient pressure. The Shuttle Vacuum Chamber (583) may beevacuated or may always be evacuated when an external vacuum source isconnected to the Vacuum Port (575).

In use or in operation, the vacuum powered mechanism 560 operates by apneumatic mechanism, method or logic whereby a vacuum mechanism valvesequence includes shutting off the vacuum source from the distalcylinder chamber 81 b or the mechanism to allow the piston to return toits home position without venting the vacuum source to ambient pressure.As a result, the vacuum pressure remains consistent in the cutting andevacuation system portion of the device. The pneumatic mechanism, methodor logic for a piston system that does not require inertial mass to movethe mechanism through transition (such as a flywheel) and that uses anexternal or internal vacuum source to provide the force to causereciprocating motion in one direction and a return spring to provide theforce to cause reciprocating motion in the reverse direction may includethe following steps.

For example, a vacuum may be open to the distal Cylinder chamber 581 bwhile ambient air is closed to that chamber. The Piston 561 advances inthe distal direction, toward a distal position due to the vacuum insidethe distal cylinder chamber 521 b and ambient pressure in the proximalcylinder chamber 581 a, on the proximal side of the Piston 561. Distaladvancement of the Piston 561 compresses the Compression Spring 568,where the vacuum force should or may be great enough to overcomefriction in order to compress the Compression Spring 568.

When the piston 561 moves, the piston 561 contacts Shuttle 562 andadvances the Shuttle 562 such that the shuttle valve 564 cuts off thevacuum to the distal Cylinder chamber 581 b and the Compression Spring568 continues to compress as the Piston 561 advances in the distaldirection. Piston 561 may continue to advance distally (e.g., even afterthe vacuum is cut off to distal cylinder chamber 581 b) due to evacuatedvolume on the distal side of the Cylinder in the distal cylinder chamber581 b, which should or may be great enough to overcome friction and tocontinue compressing the Compression Spring 568 and advancing theshuttle 562 to allow ambient air to flow into the distal cylinderchamber 581 b by opening distal conduit 572 and distal cylinder chamber581 b to ambient air conduit 574.

The Piston 561 may retract in the proximal direction to a proximalposition due to the force of the Compression Spring 568 and a loss ofvacuum in the distal cylinder chamber 581 b resulting from ambient airflowing into the distal cylinder chamber 581 b. The Piston Shaft 562contacts the Shuttle and moves the shuttle in a proximal direction, thuscutting off ambient air conduit 574 and ambient air flow to the distalCylinder chamber 581 b. The Piston Shaft 562 continues moving theShuttle 562 proximally, eventually opening the distal conduit 572 anddistal cylinder chamber 581 b to vacuum port 575 such that the vacuumconnection is open to the distal cylinder chamber 581 b.

The mechanism is free to continue reciprocating as described above bycreating a pressure differential on opposite sides of the piston as longas adequate vacuum is available to the mechanism. The above steps mayrepeat as necessary such that the vacuum powered motor creates areciprocating motion unless or until the vacuum source is disconnected,turned off, or if the vacuum is inadequate to overcome the forcerequired to compress the Compression Spring and overcome the internalfriction or if the mechanism is stalled or halted.

In certain variations, Pneumatic valve instability or flutter caused bythe shuttle or shuttle valve attempting to move back and forth betweenstates, or between proximal and distal positions relative to distalconduit 572, may be reduced or eliminated by exposing one side of theshuttle valve 564 to the vacuum source and the opposite side of theShuttle valve 564 to ambient air. This will cause the Shuttle or shuttlevalve to move in the direction of the vacuum and will more fully openthe distal conduit 572 to the ambient air conduit 574, therebyconnecting the ambient air to the distal Cylinder chamber 581 b.

In certain variations, a small normal force may be imparted on theShuttle 562 to hold it in place to overcome unintended movement causedby friction against the Piston Shaft 565 or valve flutter caused byvalve instability. This small normal force may be imparted in the formof a ball plunger.

In certain variations of a vacuum powered mechanism, an adequate volumeis evacuated on the distal end of the Cylinder or from the distalcylinder chamber to cause the Piston to continue moving distally afterthe external vacuum source is shut off from the distal Cylinder chamber.The evacuated volume in the distal Cylinder chamber serves to encouragethe Piston to continue moving distally after the external vacuum sourceis shut off from the volume of the distal cylinder chamber, therebyeliminating the need for inertial mass to move the valve throughtransitions from one state to another.

The reciprocating motion of the mechanism may be utilized to actuate acutting device or to operate or actuate another device, e.g., anothermedical device. In certain variations, cutting device may be positionedby maneuvering a flexible or malleable shaft of the device e.g.,manually or automatically. The shaft may be maneuvered or positionedaround sensitive tissues or structures in the human body by changing theshape of the shaft. For example, extending or retracting an outer sheathor cannula on the shaft or advancing or retracting the shaft relative tothe outer sheath, thereby allowing improved maneuverability of the shaftaround structures or within confined spaces may be performed, e.g.,allowing a shaft's predetermined curvature to position the distal end ofthe shaft near a target site. Such mechanisms, techniques and devicesinclude those described in U.S. patent application Ser. Nos. 11/848,565,11/848,564, and 11/848,562, each of which is incorporated herein byreference in their entirety for all purposes.

Further describing operations of a variation of a mechanism asillustrated in FIGS. 5A-5B, FIG. 5A shows a starting position for themechanism with the Piston in a proximal position due to extension of theReturn Spring (568).

When external vacuum is applied to the mechanism through the Vacuum Port(575), the Shuttle Valve (564) is on the proximal side of the VacuumPort (75) and on the proximal side of the Distal Conduit (572). As aresult, the vacuum is able to fluidly communicate with the DistalCylinder Chamber (581 b) which results in evacuation of the air in theDistal Cylinder Chamber (581 b). Consequently, the differential pressureon the proximal and distal sides of the Piston (561) causes the pistonto move distally.

As the Piston (561) moves distally, it compresses the Return Spring(568) thereby storing mechanical energy. The Proximal Shuttle Seal (563)prevents leakage of ambient air into the Distal Cylinder Chamber (581b). The Shuttle (562) “dwells” in position until the Piston (561)contacts the Shuttle (562) and motivates it in the distal direction. TheShuttle Valve (564) then closes off the Vacuum Port (575) to the DistalConduit (572) thereby shutting off vacuum to the Distal Cylinder Chamber(581 b).

It may be necessary to have adequate evacuated volume on the distal sideof the chamber in the distal cylinder chamber 581 b to cause the PrimaryPiston (561) to continue translating distally after the Shuttle Valve(564) shuts off vacuum to the distal conduit 572 and the distal cylinderchamber 581 b.

As the Distal Cylinder Chamber (581) refills with ambient air, fromambient air conduit 574 via distal conduit 572 (which is now open toambient air conduit 514 as shown in FIG. 5 b), the Return Spring (568)motivates the Piston Shaft (565) proximally. The Shuttle “dwells” inposition until the Shuttle Return Surface (566) on the Piston Shaft(565) contacts the Shuttle (562) and motivates the Shuttle (562) in theproximal direction.

The Shuttle Valve (564) moves from the distal side to the proximal sideof the Distal Conduit (572) thereby opening the distal conduit 572 tothe Vacuum Port (575) to evacuate the Distal Cylinder Chamber 581 b).

The Shuttle (562) and the Piston 561 return to their proximal (starting)position and the mechanism has completed one cycle and is free tocontinue reciprocating as described above as long as adequate vacuum isavailable to the mechanism.

In any of the variations of vacuum powered mechanisms described herein,O-rings or other sealing components may be used to create a seal betweensurfaces but are not necessary if leakage around the seals is tolerable.Also, leakage around the seals may be reduced by using a lubricant ofsufficient viscosity to fill the gap between the seal and the bore inwhich it operates.

The Shuttle may be configured in several positions including concentricwith the Center Shaft, parallel to the Center Shaft, as a rotary valve,and so forth.

The vacuum powered mechanisms described herein may be utilized with orincorporated into a variety of medical devices. For example, the vacuumpowered mechanisms may be utilized to reciprocate a cutter on a distalend of a malleable shaft which may be manipulated or adjusted manuallyor automatically or a flexible shaft having a predetermined curvaturewhich is manipulated through advancement or retraction through a cannulaor other sheath as illustrated and described in U.S. patent applicationSer. Nos. 11/848,565, 11/848,564, and 11/848,562, each of which isincorporated herein by reference in their entirety for all purposes.U.S. Patent Application No. 61/360,429 is also incorporated herein byreference in its entirety for all purposes.

In certain variations of a device having a curved flexible shaft, arigid or semi-rigid straight sheath may be assembled or connected to thedevice to cause the curved, flexible portion of the shaft to straightenas the sheath is advanced over the curved section or to cause thecurved, flexible portion of the shaft to return to its curved shape asthe sheath is retracted.

In other variations, a rigid or semi-rigid curved sheath may beassembled or connected to a device or end effector having a shaft with acurved, flexible portion to direct the shaft as it is advanced throughthe curved sheath.

In other variations, a rigid or semi-rigid curved sheath may beassembled or connected to a device or end effector having a shaft with astraight, flexible portion to direct the shaft as it is advanced throughthe curved sheath. The rigid or semi-rigid curved or straight sheathesmay be assembled, connected, attached to or otherwise utilized with thecutting device. The various sheaths may be detachable from the devicesor end effectors or affixed or attached to the devices and or endeffectors.

In certain variations, the vacuum powered mechanisms described hereinmay also be utilized to reciprocate or actuate a reciprocating cutter ofa device or end effector or to operate a device having a semi-rigid orrigid, curved end effector or a rigid or stiff shaft. A cutter, endeffector and/or device may be operated by vacuum powered mechanisms orother motorized mechanisms or by hand.

FIG. 6 shows one variation of a rigid, curved end effector 4.0 or distalend of a device. The end effector 4.0 may include a scraping edge 4.1, awindow 4.6, a reciprocating cutter 4.2., and/or a blunt distal tip 4.5.The end effector 4.0 may also include a rigid shaft 4.7. The rigid shaft4.7 may have a shaft curvature section 4.3 and/or a shaft straightsection 4.4. In certain variations, a fluid line 4.8, e.g., a salineline, may be attached to the end effector 4.0 or extend along or withinthe end effector 4.0. In certain variations, the end effector, distalend of a device, and/or shaft may be rigid, stiff, substantially rigid,or semi rigid.

The end effector 4.0 may be a component of a device, e.g., a cuttingdevice or medical device. The end effector 4.0 may be positioned at adistal end of a cutting device or designed for use or attachment to acutting device, medical device, or other device. The end effector 4.0may be useful for various procedures requiring cutting and/or scrapingof a variety of tissues including soft and hard tissues.

The Scraping Edge 4.1 is typically made from a rigid material, e.g.,Stainless Steel, which may withstand cutting forces withoutsubstantially bending or deflecting the scraping edge 4.1. Othermaterials may be used as warranted by the desired clinical application.In certain variations, a semi-rigid material may be used. The ScrapingEdge 4.1 may be used to cut or scrape various soft and hard tissues,such as intradiscal nucleus tissue, Vertebral End Plates, cartilage,ligament, bone, and other soft and hard tissues. The Scraping Edge 4.1may be used to cut tissue free and/or to mobilize the tissue forevacuation through the Window 4.6 and through a lumen of the rigid shaft4.7. The tissue may be evacuated to a Filter or collection receptacle.

The Scraping edge 4.1 may be affixed or attached to the rigid shaft 4.7at any angle relative to the longitudinal axis of the Rigid Shaft 4.7.For example, the scraping edge 4.1 may be affixed or attached to theRigid Shaft 4.7 at a an angle ranging from or between 0 to 180 degreesor 0 to 90 degrees relative to an axis of the Rigid Shaft 4.7. As shownin FIG. 6, in certain variations, the Scraping Edge 4.1 may be affixedor otherwise attached to the Rigid Shaft 4.7 in a position that isperpendicular or substantially perpendicular to the axis of the rigidshaft 4.7.

Where the Scraping Edge 4.1 is rigidly affixed to the Rigid Shaft 4.7 asshown in FIG. 6, the cutting and scraping actions of the scraping edge4.1 may be accomplished by the operator manually moving the ScrapingEdge 4.1 through manual movement of the rigid shaft 4.7 or the endeffector 4.0 or a component thereof. Optionally, the cutting andscraping actions of the scraping edge 4.1 may be accomplishedautomatically or by motorized movement or operation of the rigid shaft4.7 or the end effector 4.0 or a component thereof.

In certain variations, the Scraping Edge 4.1 may be affixed or attachedto the Reciprocating Cutter 4.2, e.g., external to the Rigid Shaft 4.7,such that the scraping edge 4.1 can reciprocate in concert with thecutter (not shown). The scraping edge 4.1 may be affixed or attached tothe reciprocating cutter 4.2 at any angle relative to the longitudinalaxis of the Reciprocating Cutter 4.2. For example, the scraping edge 4.1may be affixed or attached to the Reciprocating Cutter 4.2 at a an angleranging from or between 0 to 180 degrees or 0 to 90 degrees relative toan axis of the Reciprocating Cutter 4.2. In certain variations, theScraping Edge 4.1 may be affixed or otherwise attached to theReciprocating Cutter 4.2 in a position that is perpendicular orsubstantially perpendicular to the axis of the Reciprocating Cutter 4.2.

The Scraping Edge 4.1 may be positioned at a location distal to theWindow 4.6 and/or the scraping edge 4.1 may be predominately alignedwith the Window 4.6 and/or positioned on the same side of the RigidShaft 4.7 as the Window 4.6. The Scraping Edge 4.1 may be positioneddistal or proximal to the Window 4.6. Optionally, the scraping edge 4.1may have exposed scraping surfaces at any location around the peripheryof the Rigid Shaft 4.7 or reciprocating cutter 4.2.

In certain variations, the end effector 4.0 may be built without aScraping Edge 4.1. Indeed, an end effector 4.0 may or may not include ascraping edge 4.1 depending on the desired clinical application. Incertain variations, one or more scraping edges may be positioned on anend effector, e.g., a plurality of scraping edges may be positioned onan end effector.

Still referring to FIG. 6, the Reciprocating Cutter 4.2 may bepositioned on the end effector 4.0 such that the reciprocating cutter4.2 may advance and/or retract axially past the Window 4.6 to excise andevacuate tissue or mobilized tissue. The Reciprocating Cutter 4.2 mayuse a “scissor” action against the window 4.5 or against a section ofthe rigid shaft 4.7 to excise tissue.

The Window 4.6 is an opening in the Rigid Shaft 4.7 that permits thepassage of tissue into the window 4.6 and into the path of theReciprocating Cutter 4.2 such that the tissue can be cut and/orevacuated. The Window 4.6 or at least a portion of the perimeter or anedge of the window 4.6 may serve as a cutting edge to “plane” tissue andexcise the tissue. Additionally, an edge of the Window 4.6 may provide asurface with which the Reciprocating Cutter 4.2 may scissor tissue asthe reciprocating cutter 4.2 passes by the Window 4.6.

The Reciprocating Cutter 4.2 may be powered or actuated by any of thevacuum powered mechanisms described herein. Alternatively, thereciprocating cutter 4.2 or end effector may be actuated through amechanism that is powered by hand or by other motorized mechanisms. Incertain variations, a rotating cutter may be utilized and powered by anyof the vacuum powered mechanisms described herein, by hand or by othermotorized mechanisms.

The Rigid Shaft 4.7 may serve as the primary structure and/or outerenvelope of the shaft of a device or cutting device to which the endeffector is attached. The Rigid Shaft 4.7 may be curved or straight orthe rigid shaft 4.7 may include curved and/or straight sections orportions. In certain variations, the rigid shaft 4.7 may be malleable toallow an operator or user to adjust or revise the curvature of the shaft4.7 depending on the application or use. For example, the rigid shaft4.7 may be bendable or the rigid shaft 4.7 may be annealed or softenedin order to alter the shape or curve of the rigid shaft 4.7 by hand ormachine. The rigid shaft may be annealed over the bendable portion ofits length and hard near the distal extremity to reduce the likelihoodof bending or damaging the shaft near the cutting window.

As shown in FIG. 6, a Shaft Curvature section 4.3 may be provided in therigid shaft 4.7. The rigid shaft may include one or more shaft curvaturesections. The shaft curvature section 4.3 allows the operator toposition the end effector 4.0 or the distal end of the end effector 4.0or the distal end of the cutting device or other device in an area ofanatomy outside of the line-of-sight of the user. For example, the shaftcurvature section 4.3 may allow the end effector 4.0 to be positionedwithin an intradiscal space. The radius of curvature of the rigid shaft4.7 or the shaft curvature section 4.3 may be determined duringmanufacturing or it may be operator-adjustable.

The rigid shaft 4.7 may also include a Shaft Straight Section 4.4 whichmay be located proximal to the Shaft Curvature section 4.3. The rigidshaft may include one or more shaft straight sections.

A Blunt Distal Tip 4.5 may be provided on the end effector 4.0. Theblunt distal tip 4.5 may significantly reduce, minimize or eliminate thelikelihood of the end effector 4.0 or distal end of a deviceaccidentally being advanced through or into tissue which is not theintended target. For example, the blunt distal tip 4.5 may reduce thelikelihood or minimize the risk of the end effector 4.0 or distal end ofthe device being advanced through an annulus when the end effector 4.0of a device is being used to cut intra-discal nucleus or for scrapingand/or evacuating vertebral endplate material. The blunt distal tip 4.5may cover all or a portion of the distal surface of the Scraping Edge4.1. In variations where the entire distal surface or substantially theentire surface of the Scraping Edge 4.1 is covered with the Blunt DistalTip 4.5, the Scraping Edge 4.1 may cut and/or scrape only when moved inthe proximal direction or a lateral direction and not when moved in thedistal direction. In other variations where the entire distal surface orsubstantially all of the distal surface of the Scraping Edge 4.1 iscovered with the Blunt Distal Tip 4.5, the Scraping Edge 4.1 may cutand/or scrape in the distal direction or it may cut and/or scrape in thedistal direction in a limited manner.

In certain variations, a fluid line 4.8 may be affixed or attached tothe external or outside surface of the Rigid Shaft 4.7 as shown in FIG.6. Optionally, the fluid line 4.8 may be contained inside the RigidShaft 4.7 by a separate lumen within the rigid shaft 4.7 or by allowingfluid to flow through the main shaft lumen. The fluid Line 4.8 allowsfluids, e.g., saline, water, air, etc., to flow from a source of fluidexternal or internal to a device to the distal end of the end effectoror the distal end of a device or cutting device.

A scraping edge 4.1 may be provided or located on an end effector 4.0having a rigid shaft 4.7, where the rigid shaft 4.7 and scraping edge4.1 allow side or axial forces to be applied to the rigid shaft,scraping edge, end effector and/or to a device attached to the endeffector to effect scraping or cutting of tissue in a vertebral disc ortissue in another area of the anatomy, while minimizing or preventingdeflection or bending of the end effector, shaft or scraping edge. Arigid end effector having a rigid shaft and/or scraping edge may permitor provide effective scraping and/or cutting of a target tissue.Optionally, a scraping edge may be positioned on the distal end of aflexible, semi-rigid or less rigid shaft or end effector and side forcesmay be applied to the scraping edge and shaft to effect scraping. In anyof the above variations, axial advancement and retraction of thescraping device and/or end effector may result in the scraping orbreaking up of tissue, such as vertebral disc tissue. Optionally, one ormore scraping edges may be positioned adjacent to the cutting window toposition the scraping edge nearly perpendicular to the direction ofmotion when a curved shaft is used.

In certain variations, an apparatus for scraping tissue in a subject isprovided. The apparatus includes an end elector. The end effectorincludes a scraping edge positioned on a distal end of the end effectorand one or more scraping wings, edges or protrusions positioned at anangle relative to the scraping edge such that the end effector may beactuated in a back and forth motion approximately perpendicular to thescraping edge to scrape or gather tissue, and/or actuated in a back andforth motion approximately perpendicular to the scraping wings to scrapeor gather tissue. The scraping wings may serve to collect tissue at thecutting window opening to improve resection.

In certain variations, the end effector may include a scraping edgepositioned on a distal end of the end effector and one or more scrapingwings positioned at an angle relative to the scraping edge such that thescraping edge and scraping wings can provide a scraping motion indifferent directions.

FIG. 7 shows another variation of an end effector 704 or distal end of acutting or scraping device. The end effector 704 may include a scrapingedge 701, a window 706, a reciprocating cutter 702, and/or a bluntdistal tip 705. The reciprocating cutter may be positioned within theend effector. The end effector 704 may include a rigid or flexible shaft707. The end effector may include one or more wings 708 positioned at anangle to the scraping edge 701, e.g., such as but not necessarily nextto the window 706. The wings 708 may be used to scrape, gather and/orcut tissue.

Wings 708 may be positioned on the end effector at an angle relative tothe scraping edge 701. For example, the wings 708 may be positioned atan angle ranging from 0 to 90 degrees, e.g. at about 90 degrees,relative to the scraping edge 701. The wings 708 are positioned at anangle relative to the scraping edge 701 such that in use, the scrapingedge 701 and wings 708 may work or scrape tissue in differentdirections. The end effector 704 may be used to cut or scrape a varietyof tissues in various regions of the body. For example, the end effectormay be utilized to cut, scrape and/or gather tissue in a spine or spinaldisc, e.g., to perform a discectomy.

In the variations described herein, the dimensions of the end effectors,shafts, devices, and/or the various components of the end effectors,shafts or devices are merely exemplary in nature and are not intended tobe limiting. It is also contemplated that in certain variations, one ormore of the various components of the end effectors or the devices, orone or more of the end effectors or the devices may be provided orutilized.

In certain variations, the various sheaths described herein for guidinga shaft or end effector may be used with a device or end effector havinga curved or straight flexible or rigid shaft.

The cutting devices or scrapers described herein may be utilized toperform a discectomy or other spinal procedures. Additionally, thedevices described herein may be utilized or provide methods forresecting, excising and/or removing tissue or soft tissue from variousregions in a patient's or subject's body. For example, the devicesdescribed herein may be utilized to excise and/or remove or evacuatevarious tissues or cells including, but not limited to: nasal tissue,for example, nasal polyps; eye tissue; tissue in various gynecologicalprocedures; tumors, e.g., cancerous tumors in the lungs, liver, and inother vital organs; and tissues or cells from other areas in a patientor subject.

An end effector with a reciprocating or “fixed” Scraper edge 4.1, aReciprocating Cutter 4.2, and/or a Rigid Shaft 4.7 (as shown in FIG. 6)or an end effector of FIG. 7 may be useful for excising and/orevacuating various tissues. Such tissues include tissues within the fullspectrum of consistency ranging from soft tissues, such as intradiscalnucleus pulposis, to tough tissues, such as End Plate cartilage andligament, to hard tissues, such as bone. For example, the end effectormay be used to prepare the intradiscal space for vertebral fusionprocedures where, e.g., it may be desirable to remove the intradiscalnucleus pulposis and End Plate cartilage and scrape the underlying boneto cause bleeding of the bone to promote healing and fusion between thevertebral bodies and implant.

In certain variations, an end effector having a Rigid Shaft, aReciprocating Cutter 4.2, and/or with or without a Scraping Edge, may beuseful for excising and/or evacuating tissues in procedures such as aforamenotomy, where it is desirable to decompress an emanating nervethat passes through a stenosed foramen. The end effector having acurved, rigid shaft with or without a Scraping Edge (4.1) may be capableof reaching into the foramen and exposing the Window (4.6) to the insidesurface of the foramen such that the reciprocating cutter 4.2 and/or thescraping edge 4.1 may excise tissue. The end effector may be utilized inboth “open” and percutaneous surgical procedures.

Optionally, an end effector or device having a flexible shaft may beused in the tissue excising, scraping or evacuating procedures describedabove.

In certain variations, a device may include or a method may utilize acutter positioned at the distal end of a flexible shaft that has apreformed or predetermined curvature. The shaft may be adapted forinsertion into a cannula or sheath where the distal end of the shaft mayadvance from the cannula (by advancing or retracting the cannula and/orthe shaft relative to each other) toward a target site and the shaft maybe configured to allow its predetermined curvature to position thedistal end of the shaft near the target site, for example, by revertingor beginning to revert to its predetermined curvature upon exiting thecannula or sheath.

The devices described herein include a mechanism powered by a vacuumsource. The devices may be used for applications where a source ofvacuum is present. For example, a source of vacuum is frequentlyavailable when medical procedures are performed. Many medical devicesutilize a reciprocating mechanism to perform their function. The devicesdescribed herein may be useful in procedures where evacuation oraspiration is necessary and the device may include evacuation oraspiration features in combination with a vacuum powered reciprocatingmechanism.

In certain variations, a device using an external or internal vacuumsource to power a reciprocating mechanism that is connected to a cutterthereby causing the cutter to reciprocate may include a “Y” connectionwithin a handle that connects the vacuum source to both the cutterevacuation tube and the vacuum powered mechanism. As a result, thevacuum performs several functions within the device, such as: powers themechanism which causes the cutter to reciprocate, draws tissue into acutting window such that it may be excised, and/or evacuates the excisedtissue to a location external to the device, while maintaining aconsistent vacuum pressure even when the vacuum source is shut off tothe mechanism during reciprocation.

In certain variations, a cutting device implements a pneumatic logic ora method utilizes a pneumatic logic to operate a cutting or otherreciprocating device whereby a vacuum mechanism valve sequence shuts offthe vacuum source from the mechanism to allow a piston to return to itshome position without venting the vacuum source to ambient pressure. Asa result, the vacuum pressure remains consistent in the cutting andevacuation system portion of the device.

In certain variations, a method includes maneuvering a flexible shaftaround sensitive tissues or structures in the human body by changing theshape of the shaft by extending or retracting an outer sheath on theshaft thereby allowing improved maneuverability of the shaft aroundstructures or within confined spaces. Such a shaft and sheath may beincorporated in any of the devices or vacuum powered devices describeherein.

In certain variations, a semi-rigid or rigid outer sheath positionedover the flexible curved shaft that is used to change the radius ofcurvature of the curved shaft may be provided. The radius of curvatureof the shaft increases when the straight and rigid sheath is extendedover the curved portion of the shaft, whereas the radius of curvature ofthe shaft returns to its precurved shape when the sheath is retractedfrom the curved portion of the shaft.

In certain variations, an electrically resistive, or bipolar ormonopolar electrocautery system is included on the distal tip of theshaft that allows the physician to cauterize tissue to control bleedingat the operative site. The electrocautery system may be powered by wiresthat run the length of the shaft through an internal lumen within theshaft.

In certain variations, a cutting device utilizing any of the variationsof vacuum powered mechanisms described herein results in automaticactuation of a cutter positioned on a flexible or rigid shaft, therebyproviding a vacuum powered cutter. The vacuum mechanism for actuatingthe cutter may enable-controls to be utilized for other functions orfunctions other than operating the mechanism, thereby reducing thenumber of levers or control buttons on the device. For, example, othercontrols positioned on the device may be utilized for straightening orcurving the shaft or for operating or controlling bipolar systems forcauterizing.

In one variation, the device may include a handle having a trigger.Actuation of the trigger may cause a cannula or sheath positioned over aflexible shaft extending from the handle to either extend or retract,depending on whether the trigger is pressed or released. The extensionor retraction of the cannula may cause the flexible shaft to straightenor curve. The device may include a roller ball, knob or other controlmechanism for adjusting or for turning on/off vacuum flow or ambientflow to thereby regulate cutting speed. For example, such a knob orroller ball may be positioned on the cutting device such that the knobor roller ball may be manipulated by a thumb or other finger on the handholding the handle of the device or on a free hand of the user. Thus,the cutting device can by used with one hand, freeing up the other handof the user or physician for other uses. A single vacuum line may attachto the device, which both evacuates excised tissue and powers themechanism. For example, a “Y” connection within the handle of the devicemay connect the vacuum source to both the cutter evacuation tube and thevacuum powered mechanism, where the device maintains a consistent vacuumpressure or force at the cutting window for evacuating excised tissueduring operation of the mechanism.

The mechanism according to the variations described herein may actuate acutter automatically by using a mechanism powered by an external vacuumsource. The external vacuum source may be connected to the device toprovide suction to facilitate tissue cutting and evacuation, therefore,the use of the external vacuum source to power the cutter is completedwithout requiring an additional power source such as electricity,compressed air, or mechanical input by the operator.

Because vacuum power is used to actuate the cutter, operator fatigue maybe reduced as compared to a system requiring the operator to manuallyactuate the reciprocating mechanism such as via button or triggermechanism. Also, the use of vacuum to power the cutter actuation maysignificantly increase the rate at which the cutter actuates, therebyreducing the time required to complete tissue resection.

The use of vacuum power to actuate the cutter may allow the control forthe rate of actuation to be moved from a “primary” position such as atrigger or button to a “secondary” position on the device handle. As aresult, the primary control may be utilized to control the rate at whichthe cutter mechanism actuates or as a control for the radius ofcurvature of the shaft, or as a control for an electrocautery system.

A knob, trigger, roller clamp, or other control interfaces may be usedto control the rate at which the vacuum mechanism reciprocates. Theseoptions allow the device to be designed in a variety of configurationsto suit various surgical specialties or personal preferences.

The various pneumatic logic sequences utilized by the systems describedherein may optionally maintain high vacuum throughout the engine cycleby never venting the vacuum source to the atmosphere. As a result, thevacuum pressure that facilitates cutting and evacuation may not decreasewhile the mechanism reciprocates.

A single tube from the vacuum source to the device to serve thefunctions of tissue cutting, evacuation and to power the mechanism whichactuates the reciprocating cutter may be utilized. The single tube fromthe vacuum source simplifies connections required for device operationand reduces the number of tubes attached to the device thereby reducingthe “clutter” and unwieldiness caused by multiple tubes and wireconnections to the device.

In certain variations, a second source of vacuum may be provided suchthat separate vacuum sources power the mechanism and provide suction tothe distal end of the cutting device or end effector for excising and/orevacuating tissue. In certain variations, one or more vacuum sourcesand/or one or more tubes or conduits connecting a vacuum source to adevice to supply suction to the device and/or to power the device may beutilized or provided.

A cannula may be used on the flexible shaft to change the radius ofcurvature on the shaft in a range from nearly straight to curved in anarc of 180 degrees. This allows the operator to optimize the curvatureof the shaft based on the patient anatomy. The operator can increase ordecrease the force between the shaft and the target tissue being excisedby extending or retracting the cannula to increase or decrease thenatural radius of curvature of the shaft.

Optionally, an electrically resistive, or monopolor or bipolar cauterymay be used on the distal tip of the devices described herein to allowthe operator to cauterize tissue to control bleeding at the site wheretissue has been excised. This feature obviates the need to remove thedevice from the operative site to replace it with an electrocauterydevice. This improves speed and ease-of-use for the operator whilereducing blood loss for the patient.

The devices described herein may be manufactured using low costcomponents and assembly techniques; as a result, the cost of the deviceis much lower than a similar device which utilizes an electric motor.

The devices described herein may have a relatively low mass and may beeasily sterilized using commonly used sterilization techniques such as,e.g., electron beam radiation, gamma radiation, or Ethylene Oxide gas.

Other variations of vacuum powered devices and methods are providedbelow. For example, a medical device may utilize a mechanism powered byan external source of vacuum to perform one or more function(s) throughreciprocating motion output by the mechanism. The device may excise andevacuate tissue. The device may have a single attachment to an externalvacuum source wherein said vacuum provides power to the mechanism andassists in excising tissue. The device may have a single attachment toan external vacuum source wherein said vacuum provides power to themechanism and assists in evacuating tissue. The device may utilize amechanism that does not utilize inertia of mass to transition pastvalves to change state. The device may not vent the external vacuumsource to ambient air at any time during its cycle thereby causing adrop in vacuum within the device. The device may include a flexibleshaft that has a preformed curvature on the distal portion and astraight rigid or semi-rigid cannula around the outer diameter of theshaft; the radius of curvature of the shaft may be changed by slidingthe cannula over the distal curvature whereby the radius of curvature isincreased when the cannula is extended over the distal curvature and thedistal curvature returns to its' preformed curvature when the cannula isretracted from the distal curvature. The device may include a monopolarelectrode or bipolar electrodes on or near the distal extremity. Thedevice may have a single connection to an external vacuum source thatpowers a vacuum powered mechanism and evacuates excised tissue. Thesingle connection to an external vacuum source may also use vacuum todraw tissue into a cutting window to present tissue for the purpose ofexcising said tissue.

A medical device may include a mechanism powered by an external vacuumsource wherein said mechanism is comprised of a piston that is set intomotion by creating differential pressure on either side of the pistonwherein one side of the piston has ambient air and the air on the otherside of the piston is at least partially evacuated. The mechanism mayinclude a valve component that opens the volume next to the Pistonalternately to ambient air or vacuum. The valve component may beactuated as a result of translation of the Piston wherein the Pistonacts upon the valve to cause it to open or close the fluid connectionsto ambient air or to the external vacuum source.

A method for causing a reciprocating mechanism powered by vacuum totransition past valves to change states wherein an adequate volume ofair has been evacuated prior to closing the valve to the external vacuumsource such that the mechanism continues to move into the evacuatedvolume such that the valve fully transitions to open the source ofvacuum to a different volume may also be provided.

The method may include the following logic sequence: Vacuum open to thedistal side of the Cylinder, ambient is closed to distal; ambient opento proximal side of Cylinder, vacuum is closed to proximal; Pistonadvances toward distal position due to the vacuum inside the distal sideof the cylinder and ambient pressure on the proximal side of the Piston;Piston contacts Shuttle and advances it toward the distal position;Vacuum Seal on Shuttle moves from proximal side of Vacuum Port to thedistal side of the Vacuum Port while the Distal Seal on the Shuttleopens the ambient air to vent the distal side of the Cylinder to ambientpressure and the Proximal Seal on the Shuttle closes the ambient airvent to the proximal side of the Cylinder; Piston reverses direction andmoves in the proximal direction due to the vacuum inside the Cylinderproximal to the Piston and ambient air on the distal side of the Piston;Piston contacts Shuttle and advances toward the proximal position;Vacuum Seal on Shuttle moves from distal side of Vacuum Port to theproximal side of the Vacuum Port while the Proximal Seal on the Shuttleopens the ambient air to vent the proximal end of the Cylinder toambient pressure and the Distal Seal on the Shuttle closes the ambientair vent to the Distal side of the Cylinder. The above steps may repeatunless the vacuum source is disconnected, turned off, or if the vacuumis inadequate to overcome the force required to move the Piston.

Optionally, the method may include the following logic sequence: Vacuumopen to the distal side of the Cylinder, ambient is closed to distal;ambient open to proximal side of Cylinder; Piston advances toward distalposition due to the vacuum inside the distal side of the cylinder andambient pressure on the proximal side of the Piston; Piston contactsShuttle and advances it toward the distal position; Vacuum Seal onShuttle shuts off vacuum to the distal side of the Piston and continuesto move distally thereby opening the ambient air supply to the distalside of the Piston; Return Spring motivates the Piston in the proximaldirection due to the equalization of air pressure on both sides of thePiston; Piston Shaft contacts Shuttle and motivates it in the proximaldirection; Shuttle Seal on the Shuttle shuts off ambient air supply tothe distal side of the Piston and opens the vacuum to the distal side ofthe Piston. The above steps may repeat unless the vacuum source isdisconnected, turned off, or if the vacuum is inadequate to overcome theforce required to move the Piston.

In another variation, a medical device includes a reciprocating cuttingblade such as is used to excise and evacuate tissue that uses areciprocating mechanism powered by an external vacuum source that may beused for medical procedures where a source of vacuum is present.

The above arrangements, materials, and dimensions for the vacuum poweredmechanisms described herein are exemplary and are not intended to belimiting.

Each of the individual variations described and illustrated herein hasdiscrete components and features which may be readily separated from orcombined with the features of any of the other variations. Modificationsmay be made to adapt a particular situation, material, composition ofmatter, process, process act(s) or step(s) to the objective(s), spiritor scope of the present invention.

Methods recited herein may be carried out in any order of the recitedevents which is logically possible, as well as the recited order ofevents. Furthermore, where a range of values is provided, everyintervening value between the upper and lower limit of that range andany other stated or intervening value in that stated range isencompassed within the invention. Also, any optional feature of theinventive variations described may be set forth and claimedindependently, or in combination with any one or more of the featuresdescribed herein.

All existing subject matter mentioned herein (e.g., publications,patents, patent applications and hardware) is incorporated by referenceherein in its entirety except insofar as the subject matter may conflictwith that of the present invention (in which case what is present hereinshall prevail). The referenced items are provided solely for theirdisclosure prior to the filing date of the present application. Nothingherein is to be construed as an admission that the present invention isnot entitled to antedate such material by virtue of prior invention.

Reference to a singular item, includes the possibility that there areplural of the same items present. More specifically, as used herein andin the appended claims, the singular forms “a,” “an,” “said” and “the”include plural referents unless the context clearly dictates otherwise.It is further noted that the claims may be drafted to exclude anyoptional element. As such, this statement is intended to serve asantecedent basis for use of such exclusive terminology as “solely,”“only” and the like in connection with the recitation of claim elements,or use of a “negative” limitation. Unless defined otherwise, alltechnical and scientific terms used herein have the same meaning ascommonly understood by one of ordinary skill in the art to which thisinvention belongs.

This disclosure is not intended to be limited to the scope of theparticular forms set forth, but is intended to cover alternatives,modifications, and equivalents of the variations described herein.Further, the scope of the disclosure fully encompasses other variationsthat may become obvious to those skilled in the art in view of thisdisclosure. The scope of the present invention is limited only by theappended claims.

1. A vacuum powered tissue cutting device comprising: an elongate shafthaving a proximal end, a distal end and a lumen defined therein, whereinthe distal end has an opening for receiving tissue; a cutter positionedwithin the elongate shaft, wherein the cutter is configured to bereciprocated to cut tissue; a chamber coupled to the proximal end of theelongate shaft such that the elongate shaft remains fixed relative tothe chamber, the chamber having a mechanism positioned therein, whereinthe mechanism is powered by suction created by a vacuum source such thatthe mechanism produces a reciprocating motion which causes the cutter toreciprocate; and wherein the mechanism comprises a piston and a valve,wherein the suction is applied to both sides of the piston in analternating manner to cause the piston to reciprocate which causes thecutter to reciprocate, wherein the piston is coupled to the valve by alinkage mechanism that translates motion from the piston to the valve.2. The device of claim 1, wherein the mechanism is powered solely bysuction created by the vacuum source.
 3. The device of claim 1, whereinsuction from the vacuum source draws tissue into the opening
 4. Thedevice of claim 1, wherein the cutter is configured to reciprocate pastthe opening in the elongate shaft to cut the tissue in the opening. 5.The device of claim 1, wherein the device is configured such that cuttissue is evacuated through an evacuation lumen in the elongate shaft bysuction created by the vacuum source.
 6. The device of claim 1, whereinthe device is configured to receive suction from a single vacuum sourcewhich supplies suction for evacuation and for powering the mechanism. 7.The device of claim 1, wherein the elongate shaft has a lumen fordelivering irrigant to the distal end of an evacuation lumen in theelongate shaft, wherein the irrigant does not flow through the lumenunless suction from the vacuum source is present to draw the irrigantthrough the lumen.
 8. The device of claim 1, wherein the chamber is inthe form of an ergonomic handle.
 9. The device of claim 8, wherein thehandle is positioned at an angle relative to the elongate shaft therebyproviding a clear line of site above and/or to the side of the elongateshaft.
 10. The device of claim 1, wherein the chamber and mechanism arepositioned at an angle relative to the elongate shaft, wherein themechanism is connected to the cutter and the mechanism reciprocates thecutter in a rectilinear motion.
 11. The device of claim 1, wherein atissue collection chamber is integrated in the device such that removalof the chamber disables the device
 12. The device of claim 1, whereinthe distal end of the shaft includes a malleable portion, wherein thecutter is reciprocated within the malleable portion.
 13. The device ofclaim 1, wherein the mechanism is powered by vacuum available in aphysician's office.
 14. The device of claim 1, wherein the cutter is acutting blade and the cutting blade is not exposed on an outside of theopening to provide safety to patients.
 15. The device of claim 1,wherein the vacuum powered mechanism reciprocates at a rate of less thanabout 1200 cycles/min.
 16. The device of claim 1, wherein the speed ofthe cutter ranges from 250-2500 cycles/min.
 17. The device of claim 1,wherein the linkage mechanism comprises a bi-stable switch.
 18. Thedevice of claim 1, further comprising an electrocautery wire positionedat the distal end of the elongate shaft.
 19. The device of claim 1,further comprising a lumen in the elongate shaft for delivering ananticoagulation therapy.
 20. The device of claim 1, wherein the deviceis fully disposable.
 21. A vacuum powered tissue cutting devicecomprising: an elongate shaft having a proximal end, a distal end and alumen defined therein, wherein the distal end has an opening forreceiving tissue; a cutter positioned within the elongate shaft, whereinthe cutter is configured to be reciprocated past the opening in theelongate shaft to cut tissue in the opening; a chamber coupled to theproximal end of the elongate shaft, the chamber having a cutter driverassembly positioned therein, wherein the cutter driver assemblycomprises a piston and a valve and is powered by suction created by avacuum source such that the cutter driver assembly produces areciprocating motion which causes the cutter to reciprocate, wherein thesuction is applied to both sides of the piston in an alternating mannerto cause the piston to produce the reciprocating motion, wherein thepiston is coupled to the valve by a linkage mechanism that translatesmotion from the piston to the valve.
 22. A method of cutting andremoving tissue from a subject comprising: advancing a cutting devicenext to a target tissue in the subject, the cutting device having anelongate shaft and a cutter positioned within the elongate shaft;powering the cutting device using suction created by a vacuum sourcesuch that the cutting device produces a reciprocating motion whichcauses the cutter to reciprocate; cutting tissue with the reciprocatingcutter; and evacuating the cut tissue using the suction created by thevacuum source; and wherein the vacuum powered cutting device comprises apiston and a valve, wherein the suction is applied to both sides of thepiston in an alternating manner to cause reciprocating motion andwherein the piston is coupled to the valve by a linkage mechanism thattranslates motion from the piston to the valve.
 23. The method of claim22, further comprising drawing target tissue into an opening in theelongate shaft using suction from the vacuum source, wherein the cutteris configured to be reciprocated past the opening in the elongate shaftto cut tissue in the opening.
 24. The method of claim 22, wherein theproximal end of the elongate shaft is coupled to a handle such that theelongate shaft remains fixed relative to the handle while the cutter isbeing reciprocated.
 25. The method of claim 22, wherein the cuttingdevice is powered solely by suction created by the vacuum source. 26.The method of claim 22, wherein the cut tissue is evacuated through anevacuation lumen in the elongate shaft by suction created by the vacuumsource.
 27. The method of claim 22, wherein suction is received from asingle vacuum source which supplies suction for evacuation and forreciprocating the cutter.
 28. The method of claim 22, further comprisingdelivering irrigant to the distal end of an evacuation lumen in theelongate shaft, wherein the irrigant does not flow through the lumenunless suction from the vacuum source is present to draw the irrigantthrough the lumen.
 29. The method of claim 22, wherein the cuttingdevice comprises a handle positioned at an angle relative to theelongate shaft thereby providing a clear line of site above and/or tothe side of the elongate shaft.
 30. The method of claim 22, wherein acutting device comprises a tissue collection chamber and removal of thechamber disables the device.
 31. The method of claim 22, wherein theelongate shaft includes a malleable portion and the cutter isreciprocated within the malleable portion.
 32. The method of claim 22,wherein the cutting device is powered by vacuum available in aphysician's office.
 33. The method of claim 22, wherein the vacuumpowered cutting device comprises a mechanism that reciprocates at a rateof less than about 1200 rpm.
 34. The method of claim 22, wherein thespeed of the cutter ranges from 250-2500 cycles/min).
 35. The method ofclaim 22, wherein the linkage mechanism comprises a bi-stable switch.36. The method of claim 22, further comprising treating bleeding with anelectrocautery wire positioned at the distal end of the elongate shaft.37. The method of claim 22, further comprising delivering ananticoagulation therapy to a tissue site via the elongate shaft.
 38. Themethod of claim 22, wherein the cutting device is fully disposable. 39.The method of claim 22, wherein the tissue is a polyp.
 40. The method ofclaim 22, wherein the tissue is intradiscal nucleus.
 41. A method forperforming a polypectomy comprising: advancing a cutting device next toa polyp in a subject; powering the cutting device using suction createdby a vacuum source such that the cutting device produces a reciprocatingmotion which causes the cutter to reciprocate or rotate; and cutting thepolyp with the reciprocating or rotating cutter; and wherein the vacuumpowered cutting device comprises a piston and a valve, wherein thesuction is applied to both sides of the piston in an alternating mannerto cause the reciprocating motion and wherein the piston is coupled tothe valve by a linkage mechanism that translates motion from the pistonto the valve.
 42. The method of claim 41, further comprising evacuatingthe cut polyp using the suction created by the vacuum source.
 43. Themethod of claim 41, wherein the cutting device is powered solely bysuction created by the vacuum source.
 44. A method for performing adiscectomy comprising: advancing a cutting device into a disc in a spineof a subject; powering the cutting device using suction created by avacuum source such that the cutting device produces a reciprocatingmotion which causes the cutter to reciprocate or rotate; and cutting anucleus of the disc with the reciprocating or rotating cutter; andwherein the vacuum powered cutting device comprises a piston and avalve, wherein the suction is applied to both sides of the piston in analternating manner to cause the reciprocating motion and wherein thepiston is coupled to the valve by a linkage mechanism that translatesmotion from the piston to the valve.
 45. The method of claim 44, furthercomprising evacuating the cut disc or nucleus using the suction createdby the vacuum source.
 46. The method of claim 44, wherein the cuttingdevice is powered solely by suction created by the vacuum source.